World champion Ronnie O'Sullivan made a storming start to his bid for a fifth Masters title on Tuesday evening with a 6-1 victory over tournament debutant Robert Milkins.

The 38-year-old thrashed Milkins 6-0 in the UK Championship last month at York's Barbican Centre and was similarly ruthless in this first-round clash at the Alexandra Palace, without ever really needing to hit top gear.

The emphatic triumph set up a quarter-final meeting with either Barry Hawkins or Ricky Walden.

A 48 break put O'Sullivan in the ascendancy in the opening frame, which he went on to clinch by clearing the colours.

A missed red to the middle pocket from Milkins allowed the 'Rocket' in for an 84 break which secured frame two, and the one-way traffic continued thereafter as Milkins struggled to get a foothold in the match.

A 91 break, which turned out to be his highest of the evening, in frame four helped O'Sullivan move to 4-0 at the interval - much to the delight of his supporters in the audience, including former Masters champion Jimmy White.

The five-time world champion looked on course to whitewash his beleaguered opponent when he extended that advantage to 5-0 on the resumption courtesy of knocks of 62 and 59.

Milkins avoided the ignominy of another 6-0 rout by getting his name on the board with a 47 break in a scrappy sixth frame, the Gloucester man punching the air in mock celebration, but that merely delayed the inevitable as O'Sullivan sauntered into the last eight.

Earlier on Tuesday, 2005 world champion Shaun Murphy produced a stunning comeback from 4-2 down to advance with a 6-4 triumph over Ding Junhui.

Murphy, runner-up here two years ago, will play 2011 runner-up Marco Fu in the quarter-finals, the Hong Kong man having beaten Judd Trump 6-5 in the first round on Monday.

There was a delayed start to the Tuesday afternoon session after the arena was plunged into darkness by a power-cut.

When play belatedly got under way at 2.20pm - 80 minutes late - Ding made a flying start and soon found himself 2-0 up thanks to breaks of 99 and 84.

Murphy fought back, though, and knocks of 71 and 64 got him back on level terms at the interval.

In a topsy-turvy encounter, Ding swiftly regained his two-frame lead but then missed a couple of relatively straightforward pots for 5-2, and instead a break of 56 from Murphy allowed the Englishman to close to 4-3.

Ding's composure had gone and he looked a defeated man. He was still ahead, but Murphy had the bit between his teeth.

The Chinese player could have re-established his two-frame cushion in frame eight but missed a late red with the rest and a 46 clearance from Murphy made it all square at 4-4.

Murphy went ahead for the first time in the match by edging frame nine, capitalising when Ding was unable to gain position on the yellow, and never looked likely to relinquish the upper hand.