Usain Bolt has conceded that he was not at his best in the 100m heats at the World Athletics Championships in Beijing.
The 29-year-old had a slow start to his race, but still won with relative ease by recording a time of 9.96s to reach the semi-finals.
Bolt feels that there is plenty more to come from him in the competition as he looks to retain his world title.
"It wasn't as great as I wanted it to be, but I wasn't expecting the first one to be great," Bolt told BBC Sport.
"I wasn't trying to run fast. I wanted to save as much energy as possible. I am in wonderful shape."
The Jamaican will compete in the semi-finals later today.