Live coverage on this website, Radio Five Live and BBC television (BBC TWO: 1800-1900/2000-2100 BST; BBC ONE: 1900-2000 BST) Malcolm sees off Devonish Malcolm in kidney scare

Malcolm had a kidney illness at the Athens Olympics but won the 200m at the European Cup in June and has qualified for next month's World Championships.

On Friday, he will race some of the world's best in the London Grand Prix.

"It's good to train with someone of Darren's class. He has a lot of self-belief and that has rubbed off on me," Malcolm told BBC Radio Five Live.

"It was hard recovering from illness as I couldn't train with the intensity I wanted.

"I also had to cope with the disappointment of missing out on the [Olympic gold medal-winning] relay team.

Friday is a good opportunity to race against the best in the world Christian Malcolm

"But I realised the only way to realise my dream was to work hard.

"The last four years have gone by so quickly and I'm no longer the young, promising talent - it's time to deliver and fulfil my potential.

"I hoped before the age of 24 or 25 I'd have a couple of medals but it's not the case.

"This year is a comeback year for me and it's going well so far. But because I ran 20.16 seconds [at the European Cup], I'm not saying 'I'm going to win the Worlds'.

"But Friday is a good opportunity to race against the best in the world.