Sir Chris Hoy's dream of defending his Olympic gold medal in the men's individual sprint is slipping away after he was beaten by Jason Kenny in Saturday's semi-final at the Track World Championships in Melbourne.

36642 - Kenny pips Hoy in crucial sprint semi-final

Hoy, who won three gold medals in Beijing four years ago, is battling with compatriot Kenny for the one British squad place available for the men's sprint at London 2012. Both men, prior to this weekend's tussle, acknowledged that the result in Melbourne would likely determine who gets picked by the selectors.

If that proves to be the case, Kenny will by Team GB's sole representative in the men's sprint after he powered to a 2-0 victory in the semi-finals. Kenny now advances to a rematch of the 2011 final against France's Gregory Bauge.

Hoy was edged out by a tyre's width in the first battle of Saturday's best-of-three encounter. He then attempted to set the tone in the second, but the younger Kenny was in supreme form and flew past his rival.

It was hardly a surprise after Hoy had struggled through his heats on Friday, and now he must contest the bronze medal against the other beaten semi-finalist Shane Perkins in a fight for third.

Elsewhere, Victoria Pendleton only managed sixth place in her second round heat of the women's keirin, meaning she misses out on the final. The 2007 champion won her sixth sprint title on Friday but that appeared to have taken its toll 24 hours later.

There was better news for Laura Trott in the women's omnium, the 19-year-old claiming gold for Britain's fifth of the event. Trott held her nerve in the final discipline, the 500m time-trial, defeating Australia's Annette Edmonson by three points. Victory was Trott's first individual world title, and she is feeling confident heading to London 2012.

"I couldn't ask for much more coming into London," she said. "I didn't expect to win. I thought maybe I would pick up a medal, because I had been in the World Cups, but to win - what more can I ask for?"

Trott, who placed third in the 3km individual pursuit discipline on Saturday, singled out her 13th-placed finish in the scratch race - during which she marked Edmondson - as the key to winning the title.

"It's such a hit-or-miss race you never know what's going to happen," Trott said. "My tactic was just to follow the Australian around all day long and when she started to move just make sure that I nipped her on the line - it was a closer race than I wanted it to be. In the 500 I just did what I always do. I nailed it."