SHANGHAI (AFP) - US sprinter Justin Gatlin sailed to victory in the men's 100m at the Shanghai Diamond league on Saturday, carrying him one step closer to an Olympic showdown with his great rival Usain Bolt.
The 34-year-old veteran, who has been dogged by controversy for previously failing two dope tests, set his fastest time of the year in Shanghai, running 9.94sec, but falling short of Femi Ogunode's 9.91sec, the fastest time so far this year.
Gatlin is seeking to dust himself off after double disappointment at the world championships last year, where after leading the world in the 100m and 200m he lost both races to Jamaica's Bolt, adding extra spice to their expected meeting in Rio.
The American, who was favoured to win in Shanghai, said after the race that a winter ankle injury had made preparations "difficult".
"I came out here to execute and I know being an Olympic year, it is a long season and my coach and I have a plan. He is training me like Mike Tyson to knock out the opposition and keep swinging."
Gatlin has failed two dope tests during his career but has returned to competition and also represented the United States at the 2012 Olympics.
He declined to confirm whether Rio 2016 would be his last Olympics appearance, saying: "If I go in thinking this is my last Olympics, I'm already gonna start thinking about winding down, and I want to stay aggressive."
Meanwhile, several false starts in the competitive 110m men's hurdles saw 30-year-old Olympic champion Aries Merritt of the United States disqualified along with Orlando Ortega of Spain.
Merritt, who made a remarkable recovery from a kidney transplant last year, walked off the track in disappointment in his quest to return to Olympic glory in Rio.
The 22-year-old world indoor champion Omar McLeod of Jamaica won the 110m hurdles, setting a new best time for the year of 12.98sec, beating the previous best he set last week in Doha.
"This is the first time I have been in a race with two false starts," McLeod said after the race.
"This is something you never experience in training."
Meanwhile, in the men's 800m, world record holder and Olympic champion David Rudisha lost in a shock defeat he attributed to a bungled start, placing fifth behind Ferguson Rotich of Kenya, who won in 1:45.68sec, his best of the season.
"It was a really bad start," Kenya's Rudisha said, explaining he lost two seconds in his first appearance at Shanghai Stadium because there were "high jumpers in the lane".
He added: "We tried to throw our hands up, but the gun went off. The guys behind us were already ahead. ... It's a pity."
But the 27-year-old brushed aside questions about the World Anti-Doping Agency's ruling that Kenya's efforts against drugs were inadequate, raising fears that the athletics powerhouse could miss Rio.
In the women's 200m, former Olympic sprint champion Veronica Campbell-Brown of Jamaica also disappointed, placing second behind Murielle Ahoure of the Ivory Coast, who won in 22.72secs.
Campbell-Brown, who is seeking to reclaim the Olympic title after winning gold in Athens and Beijing, posted a time of 22.82.
Afterwards she said: "To be honest, I'm disappointed. I've been really hitting my marks in training, but I failed to deliver. Such is life. I think maybe I need to take it a little easier in training and listen to my body a little more."
In the men's pole vault 29-year-old French indoor champion and world record holder Renaud Lavillenie was defeated by American Sam Kendricks, who soared to a 5.88m finish.
Canadian Shawn Barber, winner of the world championships last year in Beijing, placed third.
And in the final event of the night local fans roared in delight as the Chinese men's 4x100m relay team took first, setting a new meet record of 38.71sec.