Jamaican sprint star advances to 100m semi-finals but describes his race as "very bad"

Asked ahead of the IAAF World Championships what his legacy will be when he wakes up on Sunday having raced his final individual event at a major championships, Usain Bolt simply replied: “Unbeatable.”

While not many people would bet against the Jamaican sprint superstar capping an incredible career with yet another 100m world title, Bolt knows he will have to vastly improve on his heats performance from Friday evening in London in order to do so.

Although he won his heat in 10.07 to progress to Saturday's semi-finals, the 30-year-old could be seen shaking his head after the race and later explained: "I stumbled coming out of the blocks."

Describing his run as "very bad", he added: "I'm not very fond of these blocks. I think these are the worst ones I've ever experienced. I have to get this start together because I can't keep doing this."

Giving further insight, he said: "It's shaky. When I did my warm-up it (the blocks) pushed back. It is just not what I am used to. Not as sturdy or firm."

Although Bolt's run might not have been as easy as expected, the entrance he gave and the reception he received were as we have become accustomed. Dancing on the start line to huge cheers, Bolt clearly enjoyed being back on the global stage inside the stadium in which he secured such success five years ago.

"The crowd is always wonderful," said the 11-time world gold medallist. "They always show me so much love and I always appreciate being here.

"I'm excited about getting through to that final and doing my job to my best."

Among those also in the semi-finals will be a trio of Britons, as James Dasaolu was second behind Bolt in 10.13 and national champion Reece Prescod ran a PB of 10.03 for third in a heat won by Jamaica's Julian Forte, who led the qualifiers with 9.99. CJ Ujah clocked 10.07 in a heat won by Bingtian Su of China.

Christian Coleman was impressive with a heat-winning time of 10.01 clocked despite easing at the end, while his fellow American Justin Gatlin was also a heat winner with a time of 10.05, which was met with the sound of boos from some sections of the crowd.

"I am not worried about the crowds and I just focus on my start and my race," said Gatlin. "It was an easy start, very technical, smooth. My form is the best that it can be this year. I feel great. You know I had a couple of injuries this year so I just want to be the best I can be.

"Bolt looks good," he added. "He has his long legs so is not out of blocks very fast but he keeps the energy very well so that is going to count in the end."

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