The triple Olympic champion Usain Bolt looked tired and eased off 30 metres from the finish line as he won his 200 metres second-round heat to reach the semi-finals.
The Jamaican clocked 20.41 seconds after appearing even more sluggish in the morning's first round.
Without his biggest rival, the defending champion Tyson Gay who;s out with a groin injury), Bolt looks set to complete a sprint double after winning the 100 on Sunday in a world record 9.58.
Bolt says he's feeling alright, a little bit tired, but nothing a good night's rest won't cure.
Fellow Jamaican Steve Mullings, who was banned for two years before returning to racing in 2006, ran the fastest time of the heats (20.23).