Federer wins Olympics opener in three sets
Roger Federer beat Alejandro Falla 6-3 5-7 6-3 to book his place in the second round at the 2012 Olympic Games.
Federer had three match points in the second set but then suddenly crumbled, hitting shot after shot into the net.
"I've struggled against him in the past at times," Federer said.
"All of a sudden I missed the match points, things got difficult and he played a great match to come back, so I'm relieved of course. Falla is a great player, counter-punches well, plays really well and made things really difficult for me."
Federer made a solid start, breaking his opponent to secure the first set 6-3.
The second set began in a similar vein, and at 5-3 Federer looked on track to wrap up the win. But a string of errors saw Falla seize the opportunity to fight back, saving three match points and breaking the 30-year-old twice to take the set and force a decider.
Normal service appeared to be resumed on the sun-drenched court at the start of the third set, as the Swiss broke his opponent in the opening game. But the world number 51 swiftly broke back to level at 2-2.
Federer broke again to go 4-3 up, then held serve to force Falla to serve to stay in the match.
Buoyed by chants of "Let's go Roger, let's go", Federer didn't let the chance slip away from him this time, looking decidedly relieved to secure his victory.
In the next round, Federer will meet Julien Benneteau.