By Rosalba O'Brien

LONDON (Reuters) - The shine looked to be coming off British diving and Olympics poster boy Tom Daley on Friday, as he narrowly qualified for the men's 10-metre platform semi-finals, coming dangerously close to crashing ignominiously out in the heats.

Throughout the six dives he rarely looked to be performing at the level required to seriously challenge China's Lin Yue or Qiu Bo for a medal, and his fate seemed sealed on his fifth dive, a back three and a half somersault, when he entered the water bent.

He did just enough on his final dive to ensure he finished fifteenth in the field of 32, with the top 18 going through to the semi-finals on Saturday.

"Towards the end of my list my legs were starting to fail on me and I was feeling tired, I wanted it to be over and just wanted to make the semis," Daley told reporters.

Daley is a household name in Britain after he competed at the Olympics in Beijing aged 14, before going on to win the platform world title at 15.

But he has been criticized for his focus on media appearances and sponsorship deals, which his Russian performance director Alexei Evangulov said had impacted his ability to live up to his potential.

The preliminary contest at the Aquatics Centre was competitive from the very first dive, when Russia's Gleb Galperin nailed an inward three and half somersault to score 88 points.

Beijing gold medalist Matthew Mitcham from Australia qualified in ninth position, while world championship silver medalist, American David Boudia, just squeaked into 18th.

Daley's synchro partner Pete Waterfield failed to reach the semi-finals.

Qiu and Lin qualified in the top two places, just ahead of Germany's Sascha Klein.

"It was a tough competition," said Daley.

"I've done my job today, not by the most comfortable of margins but I'm through to tomorrow and tomorrow is a new day."

(Editing by Greg Stutchbury)