Bernard Lagat finally claimed a global title as he took gold in the men's 1,500m.
So often the nearly man at World Championships and Olympic Games, the Kenyan-born American surged to the front in a sprint finish down the home straight to claim victory in 3mins 34.77secs.
Rashid Ramzi, the defending champion, had to settle for silver on this occasion with Kenya's Shedrack Kibet Korir in third place.
The 32-year-old said: "My medal is for the United States and everyone in America."
The Olympic 2004 silver and 2000 bronze medalist, who announced he had switched citizenship in 2005, became the USA's first-ever metric mile global champion.
Lagat's team-mate Alan Webb - the fastest man in the world this year - did much of the leading around Osaka's oval stadium, but never looked happy at the front and it came as no surprise when he fell backwards on the last lap and finished eighth in 3:35.69.
The 24-year-old three-time national champion was a spectator as Lagat sealed a victory he will treasure, having been welcomed so willingly into the US camp.
"I followed the advice of my coach which was to follow the pace," said Lagat.
"So I did not go crazy at the beginning and accelerated at the end. The pace was not that slow.
"But I still paid attention so that I did not get burned."
The first man ever to score a 1,500m/5,000m double at the USA Championships added: "I executed my kick extremely well and that was the key to winning.
"Today was a perfect day. I have waited so long for that medal."
The 2003 championships saw Lagat withdrawn by Athletics Kenya after it was alleged he had used the banned substance EPO.
But the case was never proven and he returned to finish second behind Hicham El Guerrouj in the 2004 Olympic 1,500m final.
Lagat added: "I am going to inspire a lot of people in America and Kenya."
Ramzi's mood was somewhat different.
He said: "I'm very disappointed. The shape was there but I failed tactically. I didn't make my moves at the right time."
Briton Andy Baddeley was back in ninth in 3:35.95, struggling to make up ground on the last lap having reached the bell in last position.