Noah Lyles speed matched his swagger in the Paris Olympics 100-meter dash on Sunday.

The American sprint star jumped up and down and egged on the crowd before the race, then sped by the field to win the gold medal just barely.

America, I told you! he screamed into the camera.

It took a photo finish to decide the win.

Despite a mediocre start, Lyles used his raw speed to clock a personal-best 9.79 seconds, just ahead of Jamaicas Kishane Thompson, who had the same time to the hundredth of a second. But Lyles actually won by five-thousandths of a second. Fred Kerley of the U.S. finished third in 9.81 seconds.

Lyles got off to a poor start in the semifinal on Sunday but ran with conviction. He finished second in 9.83 seconds just two-hundredths off his season best.

There were signs of trouble before that.

Lyles appeared flat in his 100-meter first-round heat and had to exert himself at the end to ensure he would qualify for the semifinal. He said later that he underestimated his competition .

He arrived in Paris as the 100- and 200-meter world champion who wants to be the face of the sport.

But Lyles blatantly choreographed effort to attain celebrity is rubbing some people the wrong way, The Athletic reported .

And that includes a teammate.

About a week earlier, he angered U.S. sprinter Quincy Hall, who won the U.S. trials 400, by suggesting he should take Halls spot on the 4x400 relay.

But against a loaded field in the final, Lyles backed up his bluster with incredible acceleration, becoming the first American to win the 100 in 20 years.