DESPITE being pushed hard by Ali Carter in the penultimate session of their last-16 clash, Ronnie O'Sullivan remains on course for a successful world championship defence.

The pair return to the Crucible tonight with the defending champion enjoying a welcome 9-7 lead after Carter, whom he defeated in last year's final, forced the pace during yesterday's session after trailing 5-3 from Saturday. But despite Carter's spirited attempt to close the gap, it is the four-time world champion who is favourite to progress to the quarter-finals.

Now, with five former world champions having already fallen by the wayside, O'Sullivan's chances of becoming the first player since Stephen Hendry, in 1996, to make a successful Crucible title defence increase by the day.

O'Sullivan started with an 86 break to extend his lead, but Carter hit back with runs of 73 and 87. But O'Sullivan's third century of the tournament – 105 – saw him edge 7-5 ahead at the interval. Carter rallied to level but O'Sullivan, who had looked decidedly shaky during the afternoon, held his nerve to restore a two-frame lead thanks to breaks of 73 and 86.

They renew their acquaintance tonight with the winner facing the victor of Stuart Bingham's match with Mark Davis.

Meanwhile, quarter-finalist Judd Trump believes some players are jealous of his meteoric success.

The player has taken three ranking titles and reached a string of finals in the past two years but the 23-year-old's rise to fame, lucrative sponsorship deals and prize money bordering on £1m has not been to the liking of some fellow professionals.

"I feel as though some people don't like the limelight I get," said Trump. "Some players say things about me, but it's the only way they can get some limelight. I let my snooker do the talking."

Former world champion Neil Robertson accused Trump of being "fake", while other critics have privately voiced their concerns over the left-hander's attitude following his breakthrough success in reaching the 2011 world final.

Shaun Murphy, the 2005 world champion, suggested Trump's over-confidence this season has increased the pressure to be successful.

"Having that air about you that you will win and it is just a question of turning up, that can put undue pressure on yourself," said Murphy.

"He's had massive success over the last few years and ripped through the field at times. The way he scores, it can be a like a knife through butter."

But Trump, who faces Murphy in the Crucible quarter-finals tomorrow, is determined to silence his critics and win the world title. "Whatever tournament I enter, I'm fully prepared to win," he added.