US sprinter Sydney McLaughlin-Levrone blew past the competition this week, becoming the first women's track athlete to run a sub-48 second 400-meter dash in almost 40 years on Thursday, when she won the event final at the 2025 World Athletics Championships in Tokyo.

The four-time Olympic gold medalist clocked a blistering time of 47.78 seconds, breaking her own US record en route to becoming the new world champion.

Notably, Dominican sprinter Marileidy Paulino — the 400-meter gold medalist at the 2024 Paris Olympics — crossed Thursday's finish line right on McLaughlin-Levrone's heels, joining the US winner in breaking the near-impossible 48-second barrier with a time of 47.98 seconds.

"You don't run something like that without amazing women pushing you to it," said McLaughlin-Levrone afterwards, crediting the impact of the other contenders on her own historic pace.

McLaughlin-Levrone's new time is now the second fastest in the sport's history, trailing only the 1985 world record of 47.60 seconds set by East Germany's Marita Koch.

Thursday's win also marked the 26-year-old's first-ever major international 400-meter flat title after historically dominating the 400-meter hurdles, making McLaughlin-Levrone the only athlete to hold world titles in both races.

"I felt that somebody was going to have to run 47-something to win this," Bobby Kersee, the sprinter's longtime coach, told The AP. "She trained for it. She took on the challenge, took on the risk. She's just an amazing athlete that I can have no complaints about."

Star sprinter Sydney McLaughlin-Levrone is reaching new heights, setting a new US record for the 400-meter race in the event's Tuesday semifinals at the 2025 World Athletics Championships in Tokyo.

The four-time Olympic gold medalist finished the flat event in 48.29 seconds, shaving more than 0.40 seconds off the previous US record of 48.70 seconds set by track legend Sanya Richards-Ross in 2006.

Both her personal best and the fastest time in the world for that event this year, McLaughlin-Levrone's performance also makes her the seventh-fastest woman of all time in the 400-meter dash — elevating expectations that she could challenge the long-standing world record of 47.60 seconds, set by then-East German sprinter Marita Koch in 1985.

Known for her dominance in the 400-meter hurdles, the 26-year-old made the decision to focus on the flat 400-meter event ahead of this year's competition. 

"I definitely wasn't expecting that time," she said afterwards. "It just shows the fitness is there. I'm excited for the finals and grateful to have taken down a record by an amazing woman."

How to watch McLaughlin-Levrone in the 400-meter final

McLaughlin-Levrone will take aim at the 2025 World Athletics Championships' 400-meter podium — and, perhaps, another record time — during the event's final on Thursday.

The US star will race against 2024 Olympic champion Marileidy Paulino and silver medalist Salwa Eid Naser when the final begins at 9:24 AM ET.

Live coverage will air on USA Network.