Ronnie O'Sullivan has admitted he will be the "underdog" in his last-16 tie against John Higgins following a commanding victory against He Guoqiang 10-2.The Chinese debutant was no match against the seven-time world champion, coming into the pair's second session 7-2 down.After a 113 break and three tidy frames, the Rocket saw off Guoqiang, who did well to take a couple of frames off O'Sullivan, given the snooker he was playing.When asked about his cues after his first round win, O'Sullivan said: "It's still rusty. I think the tip is more important than the cue to be honest.TRENDINGStoriesVideosYour Say"That's why I brought two cues. I have been saving this all year because it had a bit of life in it, and I thought if I come here and my main cue is no good, then I'd rather have a cue I like with a good tip on because I can get used to anything pretty quickly."The tip wasn't good yesterday. I did a good job considering. "A bit of a roll of the dice, a gamble, I was a bit nervous because I thought I could look a bit silly, but you have to back yourself. "I make some crazy decisions in everyone else's eyes, but they make complete sense to me, and it seems to work over the years, so I tend to listen to my own advice."LATEST SPORTS NEWSShaun Murphy demands answers from World Snooker Championship staff after controversial incidentSnooker star gives heartbreaking interview revealing struggles after World Championship exitLiv Golf row erupts as players slam controversial rumours about Bryson DeChambeauThe Rocket will face four-time world champion John Higgins in the next match, with O'Sullivan mocking the two 50-year-olds' age."A couple of oldies. I was saying, just hanging around this venue, I feel kind of old now because everyone is 22, 23, it's like walking into a creche, but we are still hanging around and having a go," the seven-time world champion told BBC Sport.He continued: "I am not the player I was and probably never will be, but as long as I can enjoy the game. I am starting to enjoy it again. "I am getting through the ball, but still not good enough to win these events. I have to rely on a bit of luck."Commenting on facing Higgins in his upcoming match, O'Sullivan said: "John loves playing me. "I think he plays better than me than I play against him. I think in a way I will be a bit of an underdog because I've hardly played over the last three years compared to John. "He's probably favourite, but it's a different type of pressure."The last-16 tie will begin on Saturday evening at 7pm, with additional sessions on Sunday evening and Monday afternoon.O'Sullivan is chasing his eighth world title, which would take him clear of Stephen Hendry's seven.Yesterday's first session saw the 50-year-old lead 7-2, as he stretched his advantage with a break of 62 before potting nine reds and eight blacks.Another century break of 100 in the last frame secured the 10-2 victory, in a dominant display from the Rocket, who is well in the mix at this year's tournament.Our Standards: The GB News Editorial Charter