Usain Bolt expressed disappointment with his performance at the Golden Spike meeting on Wednesday, despite claiming victory in his second 100 metres race of his final season.
Sprint legend Bolt is expected to retire after the World Championships in August and continued his preparations by winning in a time of 10.06 seconds in Ostrava on Wednesday.
Speaking after the race, Bolt said: "I'm not happy with the time but I'm just getting into my running, I have some training to do, work on my execution but I'll be fine.
"I'm going to get checked out by my doctor, my coach will give me some training to do and I should be fine, so I've got no worries."
Meanwhile 400m world record holder Wayde van Niekerk set a world's best time at 300m, his triumph in 30.81 seconds beating Michael Johnson's previous mark and the meet record of 30.97 set by Bolt.
Mo Farah also emerged victorious in the 10,000m race in the Czech Republic.