Ronnie O'Sullivan equals Stephen Hendry century record in winning Masters opener

The Masters champion - who is chasing a sixth title at London's Alexandra Palace - watched as Walden recovered from trailing 5-1 to 5-4 behind before finishing off the match with his second century, a knock of 116, in the final frame of an absorbing contest.

O'Sullivan's reward is a quarter-final match with Marco Fu in the last eight on Thursday afternoon.

"I could have had it earlier on," O'Sullivan told the BBC. "You start to make silly mistakes when you are chasing a record. I scraped over the line."

Seven-times world champion Hendry is part of the BBC's commentary team at the event after retiring from the circuit in 2012. He said: "I am not bothered, it was a matter of time (before it was beaten)."

O'Sullivan had thumped Walden 6-0 in the Masters quarter-finals a year ago, and looked poised for another comfortable win as he picked up five of the first six frames that included runs of 77, 91 and 100 from leading 2-1.

Walden reduced his arrears to 5-2 with a 100 of his own before pinching the eighth frame after O'Sullivan had opened with a 66.

A 73 gave Walden hope of a rousing recovery, but he missed a red early in the frame as a fluked yellow on 89 paved the way for O'Sullivan's record-equalling contribution as his fellow Englishman was left to wonder what might have been.

"I've been thinking about the record since I got within striking distance and I'm glad I've equalled it now," said O'Sullivan. "I doubt Stephen Hendry is that bothered, he's still got the seven world titles record which means more to him than anything. For me it's more about winning this tournament now.

"There's a lot of expectation because I've won back-to-back tournaments and I'm going for a third. There's a lot of pressure because the crowd in London want to see me do well. It's great to have that support but it comes with that pressure because I want to keep them happy and keep winning.

"I had spells in the match where I was strong, but I wasn't firing on all cylinders. I'm not as sharp as I was 18 months ago, I was quicker out of the blocks then.

"At the moment I'm drifting in and out, sometimes losing two or three frames in a row which is not ideal at this level. Hopefully I can raise my game and get stronger with each match."

In the evening's match, Ali Carter enjoyed a 6-1 win over Barry Hawkins as he made runs of 95 and 50 to progress to the last eight.

Carter was given the all-clear by doctors in December from lung cancer having already beaten testicular cancer.

The double World Championship finalist will face Neil Robertson in the quarter-finals.