China's Liu Xiang ended David Oliver's 20-race unbeaten run with a tremendous win in the 110m hurdles at the second Diamond League event in Shanghai.
Liu, trialling a new start, blasted out of the blocks to win in 13.07 seconds, while under-pressure American Oliver hit four hurdles as he finished second.
Britain's Jenny Meadows comfortably won the women's 800m in 2:00.55.
Jamaicans Asafa Powell and Veronica Campbell-Brown won the men's and women's 100m races in fine style.
On a day of quick starts, Powell was first out of the blocks and powered down the track to win in 9.95 seconds from America's Michael Rodgers.
"It was a good performance," said Powell. "I was not trying to push too hard because I'm not 100% fit and I didn't want to hurt myself so I was surprised with the sub-10 second time."
In the women's race, Campbell-Brown reacted so quickly to the starter's gun that BBC commentator Stuart Storey initially thought it could have been a false start.
But the sprinters were not recalled and Campbell-Brown held off the fast-finishing American Carmelita Jeter to win in 10.92 seconds.
"It was a great way to wind down my birthday," said Campbell-Brown, who turned 29 on Sunday. "I executed well and I'm pleased with my result."
Liu, who has been putting his right leg into his trousers before his left leg to help practice his new start, where he takes seven strides instead of eight to the first hurdle, was similarly pleased with his performance but admitted his new technique was not easy to master.
"It's very very difficult and it has consumed me," he said. "It's very different."
Oliver was philosophical after tasting defeat for the first time in 20 races, saying: "He didn't surprise me. I've just got to go back home and regroup.
"It was not my best performance but it wasn't terrible. I did a lot of losing before I did any winning so I can use this to build for the season."
Wigan Harriers athlete Meadows produced a dominant performance to run away with the women's 800m.
The 30-year-old overtook the pacemaker after 500m and stretched the field down the back straight, allowing her to ease down in the latter stages and win by almost one second from Morocco's Malika Akkaoui.
Elsewhere, Croatia's Blanka Vlasic got her season off to the perfect start with a straightforward victory in the high jump.
Vlasic, who has a personal best of 2.08m, was the only jumper to clear 1.94m.
"Five days ago I couldn't clear 1.85m in training and I was crying," admitted Vlasic. "I only arrived here on Saturday and I knew I wasn't in top shape so it was just my goal to win."
Kenyan Nixon Chepseba, who won last week's non-Diamond League 1500m race in Doha, outsprinted team-mate Asbel Kiprop to win in Shanghai. His time of 3:31.44 is the quickest this year.
America claimed first, second and third in the men's 400m with Calvin Smith producing the best-paced race to glide past Greg Nixon and David Neville in the final five or six strides and win in 45.47 seconds.
The men's 3,000m steeplechase also produced a tight finish with Kenya's Brimin Kipruto kicking off the final hurdle and poweing past his team-mate Paul Koech in the final 10m.
Kipruto's time of 8:02.28 was 10 seconds quicker than the previous best for 2011 and would have been the third best time last season.
And in the women's 5,000, race, Kenya's world champion Vivian Cheruiyot held off the challenge of Sentayehu Ejigu of Ethiopia and 10,000m world champion Linet Masai of Kenya to win in 14:31.92.