Lagat, 35, surged past defending champion Tariku Bekele of Ethiopia with slightly more than a lap to go and handily won in seven minutes 37.97 seconds.

Spain's Sergio Sanchez took second in 7:39.55 with Kenyan Sammy Mutahi third.

Bekele, the brother of Ethiopian distance great Kenenisa Bekele, faded to fourth.

"My kids woke up at 7 a.m in the morning to watch their daddy," Lagat said. "So I needed to show them something."

The former double outdoor world champion thrust his right arm into the air in celebration more than 20 meters from the finish and repeated it again before crossing the line in his season's best time.

Abubaker Kaki of Sudan retained his title in the men's 800, running 1:46.23 to Kenyan silver medalist Boaz Lalang's 1:46:39.

Twice world indoor champion Terrence Trammell posted the fastest 60 metres hurdles semi-final time, clocking 7.51 seconds. Cuban favorite Dayron Robles also was a heat winner.

Chinese defending champion Liu Xiang was the slowest qualifier for the final later on Sunday. He finished second to Trammell in 7.68 seconds.

(Editing Alison Wildey) - Source: Reuters