Wimbledon champion Serena Williams dismantled Jelena Jankovic in just over an hour on Centre Court to begin her Olympic campaign with a win.
The American, seeded fourth at the Games, needed a solitary break to take the opening set 6-3.
Williams continued to accelerate and broke Jankovic's serve in the first and third games of the second, racing to a 4-0 lead over the Serbian.
Jankovic did get on the board in the set but could do little to stop Williams, who broke again in the seventh game of the set to take the second 6-1 and seal the win.
The 30-year-old will face Poland's Ursula Radwanska in the second round at the All England Club.
