Alison dos Santos Runs 45.80 to Break Karsten Warholm’s 400m Hurdles World Record in Zurich

Alison dos Santos had spent the entire 2026 season beating Karsten Warholm. In Zurich, he finally took something even bigger from him.

The Brazilian produced a staggering 45.80-second performance at the Weltklasse Zurich Diamond League meeting on Thursday, breaking Warholm’s men’s 400m hurdles world record of 45.94 and becoming the fastest one-lap hurdler in history.

Warholm, whose record had stood since his extraordinary Olympic title in Tokyo in 2021, finished second in 46.69. That would ordinarily rank among the defining performances of an international season. On this night, it left him almost nine-tenths of a second behind a rival who had already beaten him repeatedly across 2026.

Dos Santos did not steal the record through one desperate lean at the line. He had effectively erased the stagger on Warholm by halfway, according to World Athletics, and continued opening the gap as the race moved through the second bend and toward the home straight.

Four days earlier in Silesia, Dos Santos had run 46.43 to beat Warholm’s 46.52. That already represented the sixth-fastest 400m hurdles performance ever recorded at the time.

Zurich made 46.43 look like preparation.

Alison dos Santos’ 45.80 World Record at a Glance

Detail	Result
Event	Men’s 400m hurdles
Meeting	Weltklasse Zurich, Wanda Diamond League
Date	August 27, 2026
Venue	Letzigrund Stadium, Zurich
Winner	Alison dos Santos, Brazil
Winning time	45.80 seconds
Previous world record	45.94, Karsten Warholm, Tokyo 2021
World-record improvement	0.14 seconds
Runner-up	Karsten Warholm, 46.69
Previous Dos Santos season best	46.43, Silesia, August 23
Status	World record, subject to normal ratification procedures

The official World Athletics report from Zurich confirms Dos Santos’ 45.80 performance and the 0.14-second improvement on Warholm’s previous world record.

The World Record Fell Before the Race Reached Its Final Crisis Point

The most striking detail from Zurich was how early the balance between the two men changed.

Warholm’s great strength throughout his career has been his willingness to attack the opening half of the race with an intensity that forces everyone else to respond. The Norwegian rarely waits for the final straight to decide a race. His opening bend, speed between the early hurdles and commitment through 200 meters have often created the gap before rivals are ready to challenge it.

The Sports Encounter saw that pattern again when Warholm won his fourth consecutive European 400m hurdles title in Birmingham in 46.63.

Zurich reversed the usual picture.

World Athletics reported that Dos Santos had made up the stagger on Warholm by halfway. Instead of trying to survive Warholm’s first 200 meters, the Brazilian had already placed himself level in effective track position.

From there, the race became something Warholm has rarely experienced at his best.

He was chasing.

Dos Santos Did Not Fade After Catching Warholm

Making up a stagger on Warholm is one thing. Maintaining that aggression through hurdles seven, eight, nine and ten is much harder.

The final 120 meters of the 400m hurdles punish every early decision. Athletes are trying to maintain sprint mechanics while fatigue changes stride length, ground contact, posture and hurdle clearance. One misjudged pattern can destroy an otherwise brilliant race.

Dos Santos did not unravel.

He kept moving away.

That may be the technical detail that separates Zurich from simply being a very fast race. The Brazilian did not need a dramatic correction late. His momentum survived the stage where most 400m hurdles races become survival exercises.

By the time he crossed the line, the stopwatch had moved into territory nobody had ever reached.

45.94 Had Been One of the Defining Records of the Tokyo Olympics

Warholm’s previous world record carried unusual historical weight.

He ran 45.94 in the Tokyo Olympic final in 2021, beating Rai Benjamin’s 46.17 in a race widely regarded as one of the greatest track events ever staged.

For five years, the number stood as evidence of how dramatically the event had evolved.

Before that Olympic final, breaking 46 seconds looked almost unimaginable.

Warholm did it.

Dos Santos has now gone another 0.14 seconds faster.

The official World Athletics all-time list now places 45.80 at the top of the men’s 400m hurdles rankings.

Dos Santos Had Been Warning Warholm All Season

The world record did not arrive from nowhere.

Their 2026 rivalry has been almost entirely controlled by Dos Santos.

He beat Warholm over 300m hurdles in Keqiao to start the season. One week later in Xiamen, Dos Santos ran 46.72 to beat Warholm’s 46.82 over the full distance.

Oslo brought another victory.

Then came Silesia.

Then Zurich.

Meeting	Dos Santos	Warholm	Winner
Keqiao, 300m hurdles	33.01	33.05	Dos Santos
Xiamen, 400m hurdles	46.72	46.82	Dos Santos
Oslo, 400m hurdles	46.89	47.40	Dos Santos
Silesia, 400m hurdles	46.43	46.52	Dos Santos
Zurich, 400m hurdles	45.80 WR	46.69	Dos Santos

The official Wanda Diamond League preview had already highlighted that Dos Santos was unbeaten against Warholm in their 2026 meetings before Zurich.

Thursday did not change that pattern.

It transformed the scale of it.

Silesia Was the Clearest Warning

The strongest indication arrived only four days before Zurich.

Dos Santos ran 46.43 at the Silesia Diamond League, beating Warholm’s 46.52 in one of the fastest combined 400m hurdles races ever seen.

At the time, 46.43 represented the world-leading mark and the sixth-fastest performance in history.

It also showed that Dos Santos was no longer simply beating Warholm tactically or catching him on a difficult day.

He was moving toward world-record pace.

The jump from 46.43 to 45.80 is enormous at this level, but the trajectory was visible.

Dos Santos was arriving in Zurich faster than he had ever been.

Warholm Had Looked Outstanding Only Two Weeks Earlier

This is why the result cannot be explained by assuming Warholm had suddenly declined.

He had just produced a championship-record 46.63 at the European Championships in Birmingham, crushing a strong field and winning his fourth consecutive European outdoor title.

The performance was one of the central stories in The Sports Encounter’s Birmingham record-night wrap.

Warholm’s 46.69 in Zurich was only 0.06 slower than that championship run.

In most races, it would have been enough to dominate.

Dos Santos ran 45.80.

That gap is what makes Zurich so important.

The world record changed because Dos Santos elevated the event rather than because Warholm disappeared from elite form.

The Rivalry Has Changed Direction

For years, Warholm represented the athlete everyone else was trying to catch.

Rai Benjamin came close.

Dos Santos joined that elite group and won the 2022 world title, but Warholm still owned the most important number in the event.

That number now belongs to Brazil.

The competitive psychology changes immediately.

Warholm is no longer racing as the world record holder.

Dos Santos is no longer the athlete trying to prove he can operate at Warholm’s historical level.

He has gone beyond it.

The Sports Encounter’s complete Birmingham 2026 review described Warholm as one of the championship’s defining repeat winners. Zurich has created the next part of that story: the champion now has to chase a record owned by his rival.

Warholm’s 46.69 Should Not Be Treated as Failure

One of the easiest mistakes after a world record is to reduce everybody behind the winner to disappointment.

Warholm still ran 46.69.

Only a tiny number of athletes in history have ever operated consistently in that range.

His 2026 season includes a 46.61 victory in London, a 46.52 in Silesia and the 46.63 European championship record in Birmingham.

The problem is not that Warholm has stopped being exceptional.

The problem is that Dos Santos has become faster.

That distinction matters because it tells us the rivalry may still have considerable room to develop rather than Zurich marking the end of Warholm’s relevance.

Dos Santos Has Turned Consistency Into a Record

His progression through 2026 makes the world record more convincing than a one-night explosion.

• 46.72 in Xiamen
• 47.11 in Stockholm
• 46.89 in Oslo
• 46.43 in Silesia
• 45.80 in Zurich

The important pattern is not that every race was faster than the one before it.

It is that Dos Santos repeatedly returned to elite territory across continents and different competitive environments.

By late August, his two fastest races had arrived within four days.

That suggests timing, form and technical execution were converging at exactly the right stage of the season.

Zurich Produced Two Hurdles World Records Within 40 Minutes

Dos Santos had barely rewritten the men’s record when the stadium witnessed another piece of history.

Masai Russell ran 12.09 in the women’s 100m hurdles, breaking Tobi Amusan’s 12.12 world record.

Less than 40 minutes separated the two performances.

Two hurdles events.

Two global records.

One evening in Zurich.

That combination places Weltklasse Zurich 2026 among the most important one-night athletics meetings of the season.

The event had already promised extraordinary depth after a summer of record performances, and TSE had been following the buildup through our report on Keely Hodgkinson’s withdrawal and Audrey Werro’s changing Zurich 800m challenge.

The meeting ultimately became much bigger than any single pre-event storyline.

The Zurich Track Became a Laboratory for Athletics’ New Ceiling

Dos Santos was not alone in pushing an event into new territory.

Mondo Duplantis cleared 6.25m in the men’s pole vault while Emmanouil Karalis reached a Greek record of 6.20m.

Russell broke the women’s sprint hurdles record.

Other races produced world-leading and national-record performances.

The important broader point is that several events are currently experiencing simultaneous improvements rather than isolated brilliance.

That trend has been visible throughout the summer, including Birmingham, where TSE documented record performances across hurdles, middle distance and field events in our Day 3 European Championships review.

What Makes 0.14 Seconds So Significant?

To a casual viewer, 0.14 seconds can sound tiny.

At 400m hurdles world-record level, it is substantial.

The event combines sprint speed, ten hurdle clearances, stride-pattern management and one of the most punishing final 100 meters in track.

Once athletes move into the mid-46 and 45-second range, finding another tenth requires improvements that may be spread across almost every phase of the race.

A slightly more efficient hurdle clearance.

One fewer deceleration step.

A cleaner landing.

Better posture through fatigue.

More speed carried through the final bend.

Dos Santos did not simply dip under 45.94.

He moved the record decisively.

The 400m Hurdles Golden Era Has Another Chapter

Men’s 400m hurdles has spent much of the last decade becoming one of athletics’ richest events.

Warholm changed the standard.

Benjamin kept pushing it.

Dos Santos joined them.

The Tokyo Olympic final accelerated the event into a new statistical era, and the following seasons produced multiple sub-47 performances from the same group of athletes.

Zurich shows that the event has not reached its final ceiling.

The athlete who once sat behind Warholm and Benjamin on the historical list is now above both.

Brazil Now Owns One of Athletics’ Most Prestigious Records

Dos Santos’ achievement also carries national significance.

Brazil has produced Olympic champions, world champions and global athletics icons, but owning the men’s 400m hurdles world record places Dos Santos in a particularly exclusive category.

His 2022 world championship had already established him as one of the country’s most important track athletes.

Zurich strengthens that position considerably.

He is no longer simply a former world champion.

He is the fastest man who has ever run the event.

Budapest Now Has an Obvious Headline Rivalry

The inaugural World Athletics Ultimate Championship arrives in Budapest from September 11 to 13.

The Sports Encounter’s guide to the Ultimate Championship explained how World Athletics is building the new event around short, high-pressure finals and direct clashes between elite athletes.

The men’s 400m hurdles now gives organizers exactly the type of matchup they want.

The new world record holder against the man whose record he took.

There is very little marketing required beyond that.

Brussels Comes First

Before Budapest, the Wanda Diamond League Final takes place in Brussels on September 4 and 5.

Both Dos Santos and Warholm had already qualified for the final before Zurich.

Warholm is chasing a fourth Diamond Trophy.

Dos Santos is chasing his third.

The competition has now acquired another layer.

Every future meeting between them begins with 45.80 on the scoreboard.

Warholm’s Response Will Be One of the Most Interesting Stories of September

Warholm has spent most of his elite career responding aggressively when challenged.

After early-season defeats in China, he publicly promised to “light a fire.”

He later ran 46.61 in London and 46.63 in Birmingham.

Those performances showed the response was real.

They were still not enough to stop Dos Santos.

The next question is different.

Can Warholm rebuild his race around chasing 45.80 rather than protecting 45.94?

Dos Santos Has Changed More Than the Record Book

World records influence racing behavior.

When Warholm ran 45.94, he showed that a sub-46 performance was possible.

Other elite hurdlers began thinking about the event differently.

Dos Santos has now pushed the target deeper.

Future 46.2 and 46.3 performances will still be extraordinary.

They will no longer sit particularly close to the world record.

That psychological distance matters.

The rest of the event has to decide whether 45.80 is an isolated masterpiece or a new destination worth planning toward.

The Birmingham Context Makes Zurich Even More Dramatic

Two weeks ago, Warholm looked untouchable inside European athletics.

He won the continental title by more than a second and strengthened a championship record that TSE had followed throughout Birmingham 2026 from its opening night.

That result did not suddenly become less impressive.

Zurich showed something different.

European dominance and world dominance are no longer the same conversation in the men’s 400m hurdles.

TSE Rivalry Scorecard: Dos Santos vs Warholm in 2026

Category	Alison dos Santos	Karsten Warholm
2026 meetings won	5	0
Best 400m hurdles time	45.80 WR	46.52 against Dos Santos
Zurich result	1st, 45.80 WR	2nd, 46.69
Major 2026 title	World-record holder	European champion
Career world titles	2022 world champion	Three-time world champion
Diamond Trophy target	Third	Fourth
Current competitive edge	Speed, momentum and head-to-head control	Championship pedigree and proven resilience
TSE verdict	Now the standard	Now the challenger

The Detail That Matters

Alison dos Santos breaking 45.94 would have been historic regardless of who finished second.

Warholm being the man behind him makes it more important.

The record did not fall years after its owner had disappeared from elite racing.

Warholm was on the track.

He ran 46.69.

He had won a European title in championship-record time only two weeks earlier.

He entered Zurich still competing near the highest level of his career.

Dos Santos beat him by 0.89 seconds and took his world record.

That gives Zurich a clarity most record changes do not have.

The old standard and the new standard raced each other directly.

The new one won.

Dos Santos had already controlled their rivalry throughout 2026, but head-to-head victories can eventually be explained through form, scheduling, tactics or individual race conditions.

45.80 cannot.

It is now the number everyone else has to chase.

Frequently Asked Questions

What world record did Alison dos Santos break in Zurich?

Alison dos Santos broke the men’s 400m hurdles world record by running 45.80 seconds at the Weltklasse Zurich Diamond League meeting on August 27, 2026.

What was Karsten Warholm’s previous world record?

Warholm held the world record at 45.94 seconds, set when he won the Tokyo Olympic final in 2021.

How much did Dos Santos improve the 400m hurdles world record?

Dos Santos improved the record by 0.14 seconds, lowering it from 45.94 to 45.80.

What time did Karsten Warholm run in Zurich?

Warholm finished second in 46.69 seconds.

Who held the 400m hurdles world record before Alison dos Santos?

Norway’s Karsten Warholm held the record from 2021 until Dos Santos’ 45.80 run in Zurich in August 2026.

How many times has Dos Santos beaten Warholm in 2026?

Dos Santos has beaten Warholm in all five of their 2026 meetings through Zurich, including the 300m hurdles in Keqiao and 400m hurdles races in Xiamen, Oslo, Silesia and Zurich.

What did Alison dos Santos run in Silesia before the Zurich world record?

Dos Santos ran a world-leading 46.43 in Silesia on August 23, beating Warholm’s 46.52 only four days before the Zurich world record.

Is Alison dos Santos a world champion?

Yes. Dos Santos won the men’s 400m hurdles world title in 2022.

Did another world record fall in Zurich?

Yes. Less than 40 minutes after Dos Santos’ 45.80, Masai Russell ran 12.09 to break the women’s 100m hurdles world record.

When is the 2026 Diamond League Final?

The Wanda Diamond League Final is scheduled for September 4-5, 2026, in Brussels.

Will Dos Santos and Warholm compete at the Diamond League Final?

Both had already qualified for the Brussels final before Zurich. Dos Santos is pursuing a third Diamond Trophy, while Warholm is seeking his fourth.

When is the World Athletics Ultimate Championship?

The inaugural World Athletics Ultimate Championship takes place in Budapest from September 11-13, 2026.