Olympic and world champion Justin Gatlin clocked 9.88 seconds to outperform joint world record holder Asafa Powell in separate 100 metres races at the Prefontaine Classic on Sunday.
Gatlin used his powerful acceleration from about 40 metres to win the first race convincingly before Powell took the second in a wind-assisted 9.93 seconds.
Gatlin matched Powell's world record of 9.77 seconds on May 12.
"It proves I am here to protect my house," American Gatlin told reporters.
"I am a patriot of America and I came here to put on a great show and that's what I did."
Cool weather and rain had threatened to slow the two sprinters.
"I stumbled the first couple of steps, but it wasn't as swift as it could be," Gatlin said. "I had two fast starters on my side (Michael) Frater and Leonard (Scott)...Me and Leonard bumped arms three times during the race, so it got a little ugly but I made it through and prevailed."
Scott was second in 10.16 seconds and Jamaican world silver medallist Frater third in 10.17.
Powell slowed over the closing stages of his race but played down injury fears.
"It was a little bit cold and I got a little scared," said the Jamaican, who missed last year's world championships with a groin injury. "There was no pressure on me in the race so I just took it easy."
Powell said Gatlin's faster time meant nothing.
"It did not prove any point," he said after defeating Olympic 200 metres champion Shawn Crawford.
SHOOK HANDS
Powell and Gatlin shook hands after Powell's race and both said they were looking forward to racing head-to-head, though a proposed June 11 meeting in Gateshead, England, has been cancelled.
"Both of us are the best in the world, so any time we meet it is going to be great," Powell said.
Gatlin said a race in London in July may be a possibility.
Two-section races like Sunday's raise more questions than they answer, Powell said.
"It means people are thinking 'Who is really the best out there?'" he said.
The meeting produced the leading performances in the world in four events, including the 110 metres hurdles where Olympic champion Liu Xiang of China clocked 13.21 seconds.
"I think this year I can run under 13 seconds," said Liu, who in 2004 equalled the world record of 12.91 seconds.
"My (sprained left) ankle is not good yet, so I can't do the best," Liu said.
The ankle was healthy enough for Liu to defeat a talented field including French world champion Ladji Doucoure (13.33) and former Olympic and world champion Allen Johnson (13.39).
Kenyan-born Bernard Lagat of the U.S. won the mile in 3:51.53, American Christian Cantwell put the shot 22.17 metres and Russian world champion Tatyana Tomashova won the women's 1,500 metres in 4:01.81.
