O'Sullivan looks to be returning to his best form

The former world number one had the better of a cagey match, compiling breaks of 55, 98, 59 and 80 on his way to a convincing victory.

He will now play the winner of the other semi-final between Stephen Hendry and Mark Stevens in Sunday's final.

"I'm surprised I'm in the final. I didn't expect to get this far," admitted O'Sullivan.

"I just came here to get a few results but I've answered a few of my own questions along the way.

"When you have a bad run of results, you start to doubt yourself - I've been full of fear all tournament.

Stephen wasn't attacking the balls from the off like he usually does Ronnie O'Sullivan

"It seems like a battle out there but at least I'm up to that battle. I'm proud of myself that I've been able to compete."

Lee could have won the eighth frame to extend the match, but went in-off the pink and O'Sullivan eventually knocked it in to clinch his place in the final.

"Stephen wasn't attacking the balls from the off like he usually does," said O'Sullivan.

"It was tough because I expected him to come flying out of the blocks but he just stalled."

O'Sullivan reached the semi-finals after comfortable victories over Stephen Maguire and Quinten Hann, before scraping past Gerard Greene 5-4 in the quarter-finals.