American Carmelita Jeter beat London 2012 gold medalist Shelly-Ann Fraser-Pryce of Jamaica in the women's 100 meter final in a time of 10.81 seconds at the Aviva Grand Prix Diamond League meet in Birmingham on Sunday.
Fraser-Pryce was 0.09 behind Jeter, the silver medalist at the London Games, with Alexandria Anderson of the United States third, 0.41 behind.
Olympic champion Aries Merritt of the U.S. ran the 110m hurdles in 12.95 seconds on his way to victory, while his compatriot Tyson Gay finished second in the 200m to Nickel Ashmeade of Jamaica.
Gay ran in 20.21 seconds, 0.09 seconds behind Ashmeade.
Double Olympic gold medalist Mo Farah of Britain won the two-mile race, the final event of the day, with a time of 8:27.24 before a jubilant home crowd.
In addition to his victory, Farah was also celebrating the birth of twin girls late Friday.
"I can't believe the year. It will never happen again like this," Farah said. "It hasn't been easy coming back from the Olympics but I'm just happy with how everything is going - two twins and two gold medals."
The 29 year-old Farah claimed he will have the names of his two newborn daughters inscribed on his two Olympic gold medals - once he and his wife have chosen names for them.
"The first born will have 10,000m and the second will have the 5,000m," Farah said.
Farah's compatriot, Christine Ohuruogu, finished second in her 400m race with a time of 50.67 seconds to Rosemarie Whyte of Jamaica, who recorded a season's best time of 50.2 seconds to claim the win.
Farah's fellow British gold medalist, Greg Rutherford, could not repeat his Olympic heroics in the long jump, finishing in third position. Russian Aleksandr Menkov won the event with a jump of 8.18 meters. American Christian Taylor finished second.
In the women's 400m hurdles, the crowd thought they had another home winner in Perri Shakes-Drayton after Jamaican Kaliese Spencer was disqualified for bringing her leg around a hurdle.
However, Spencer appealed successfully and was reinstated as the race winner.