EUGENE, Ore. — Sydney McLaughlin looked to her left and saw the numbers “51.90.” Her first thought: “Oh my gosh!”

Now, at long last, the 400-meter hurdles world record belongs to her.

On Sunday night at U.S. Olympic track trials, McLaughlin finally outraced Dalilah Muhammad to earn the victory, and the record, that Muhammad kept grabbing whenever they met. McLaughlin’s 51.90 was good enough to beat Muhammad by 0.52 seconds. It shattered Muhammad’s old world record by 0.26.

“It’s one of those moments you think about and dream about and play in your head that you’ll put it together,” said McLaughlin, who not long ago aligned with coach Bobby Kersee.

Her record was the highlight of a day that included other kinds of history.

RELATED: Too hot: Track trials come to a halt as temperatures soar

Noah Lyles won the 200 meters to punch his Olympic ticket, then celebrated by kneeling on the track and clasping his hands together: “I just stopped stressing and let my body do what it does,” he said after posting a world-leading time of 19.74 that came on the heels of some lackluster runs through the 100 and 200 rounds.

He shared the spotlight with 17-year-old Erriyon Knighton, whose third-place finish makes him the youngest male member of the U.S. Olympic track team since Jim Ryun in 1964.

JuVaughn Harrison, a 22-year-old from LSU, won not one, but two titles on the same day to become the first American to make the Olympics in both the high jump and the long jump since Jim Thorpe in 1912.

“That’s a lot of years for somebody not to do it,” Harrison said. “It’s really good for me to have my name in history like that.”

It’s an amazing enough feat on a normal day. On this day — unbelievable.

Temperatures at Hayward Field reached 108 degrees and the surface of the track exceeded 150.

It forced USA Track and Field to put a halt to the action at about 3 p.m., shortly after heptathlete Taliyah Brooks was being carted off the track in a wheelchair. Brooks was in fourth place when she went down during javelin warmups. She did not make it back, and when the competition resumed some five hours later, Annie Kunz got the win.

Much earlier in the day, Paul Chelimo won by .19 seconds in a sprint to the finish in the men’s 5,000, which had been moved to the morning to beat the heat. Much later on the track, Athing Mu won the women’s 800 and Cole Hocker edged reigning Olympic champion Matt Centrowitz in the 1,500.

McLaughlin’s race was delayed by about four hours. She said the wait “was a little bit of a throw in our plan.”

“But we were prepared for that,” she said. “Bobby always talks about Muhammad Ali, and always having to be ready for that left hook.”

In this case, it was another Muhammad — Dalilah Muhammad — who has, in her own way, been preparing McLaughlin for this day.

This marked the third straight major race in which the two squared off and a world record was set. The last two times, it was Muhammad who came out on top. It happened first two years ago on a rainy day in Des Moines, Iowa, at national championships. Then again, a few months after that at worlds in Qatar. McLaughlin ran a 52.23 at worlds, but lost by .07 seconds. That mark would have been the world record had she run it before Muhammad started rewriting the book that season.

“Dalilah is a great competitor, and I was growing into my own person,” McLaughlin explained when asked if she was deflated after running such good times, only to come in second.

She also credited a renewed sense of faith and, of course, Kersee, for this breakthrough.

Kersee is the legend who has, over the years, squeezed the most out of some of the greatest in the sport, including Allyson Felix, Jackie Joyner-Kersee and Florence Griffith Joyner.

He put McLaughlin on a new plan — getting her focused on improving her form by running shorter hurdles courses.

“It was trusting the process, and a lot of things you can’t really see coming,” McLaughlin said. “But just having the childlike faith in trusting everything is going to work out. Bobby’s really good at that.”

Muhammad said getting to the starting line in this, a year that started with injuries and a COVID-19 scare, was never a sure thing. She said she couldn’t break 55 seconds to start the season.

“Almost for a month straight, I kept asking (my coach) every day at practice, ‘Are you sure. Are you sure?’” Muhammad said. “I’m extremely grateful to be here today, and so thankful those setbacks are behind me.”

Up next is the Olympics. The finals in the 400 hurdles are set for Aug. 4. The world record in this event is always in jeopardy.

“She definitely pushes me,” Muhammad said during her interview on the track. Then, she turned to McLaughlin and said: “Congratulations, you world-record holder. It’s going to be a battle in Tokyo for sure.”