Robertson beat Cope in last season's Aberdeen Grand Prix

Australia's 25-year-old world number seven marked his return to form with an easy victory over Cope in Belfast.

"It's just nice to have won for a change. That's the best I've felt all season," he said.

"I didn't come into this tournament with much expectation, but I was really happy with the way I played."

Breaks of 60, 71, 74, 52 and 110 did the damage to earn the Cambridge-based Australian a last 16 meeting with Preston-based Ian McCulloch, who defeated 2006 Welsh Open champion Steven Lee.

606: DEBATE Who do you think will come out on top in Belfast? Saj C

Ding Junhui, who beat Ronnie O'Sullivan in last year's final, made a winning start to the defence of his title.

The Chinese player enjoyed a comfortable 5-2 win over Joe Perry to book a last-16 meeting with Scotland's Stephen Maguire.

Ding said: "There was a little bit more pressure on me because I'm the defending champion so I just wanted to win my first match.

"I've not played well so far this season so hopefully I can start to play better. I'm trying to rediscover the feeling I got when I won here last year."

Former UK and European Open champion Maguire defeated 5-0 David Gray in a repeat of the 2004 UK Championship final, which the Scot won 10-1.

The evening session at the Waterfront Hall saw wins for three former world champions.

Ireland's Ken Doherty beat Mark King 5-0, Peter Ebdon saw off Adrian Gunnell 5-2 and six-time Crucible winner Steve Davis saw off local hero Joe Swail 5-3.

"It was a good result for me, it was just what I needed after losing my last couple of first-round matches," said Dubliner Doherty.

"The first four frames were pretty scrappy, but a win is a win. You have to be able to grind out a result to get the wheels turning again."