Selby's superior safety play won the gruelling 16th frame

Selby progressed with a 9-7 win over Marco Fu, winning the clincher 76-41 after a gritty 77-minute struggle.

The previous longest on TV, 74 minutes, was between Graeme Dott and Peter Ebdon in the 2006 World Championship final.

Selby's win set up a clash with Ronnie O'Sullivan, who thrashed Jamie Cope 9-2. Stephen Maguire will face Shaun Murphy in the other Telford semi-final.

Maguire saw off Mark Williams 9-5 in the last eight, while Murphy claimed a 9-7 victory over China's Ding Junhui.

World number 11 Selby, the 2007 World Championship runner-up, was delighted with his win, if not the length of the final frame.

The Leicester player said: "Luckily, I just managed to fall over the line, so I'm chuffed to bits.

"I knew I was going to break some records (in my career), but that's the type of record I don't want to be breaking."

606: DEBATE Who do you think will reach the final? wildJONESEYE

He added: "Marco's a great player, even before he got a title under his belt (this season's Grand Prix.

"I knew he was going to be full of confidence, so it's a great win for me."

O'Sullivan produced another sensational display to beat qualifier Cope.

'The Rocket' took a 6-2 lead into the final session which soon became 8-2 as a result of breaks of 82 and 112.

The 32-year-old, who beat Mark King 9-1 in the previous round, then did enough in the next frame to secure victory.

"My break-building has been good this season, and the long-potting came together today as well," said two-time world champion O'Sullivan.

"Jamie's one of the up-and-coming players. He's got a good touch, he plays free-flowing snooker, so you try and raise your game a bit more.

"He could have quite easily done what I did to him, but I enjoyed it out there. You have to make the most of it when you play like that."

Murphy and former UK title-holder Maguire also faced each other in last month's Northern Ireland Trophy semi-finals.