The 30-time ranking event winner was given a run for his money before clinching a 6-3 victory at the York Barbican, finishing off with a 105 break.
O'Sullivan is a Sky Bet Price Boost to win the UK Championship at odds enhanced from 9/4 to 11/4!
Early runs of 80 and 117 from O'Sullivan suggested he would cruise through, before Page took advantage of the five-time champion easing off to level up at 2-2 by the interval.
If Page had a scent of an upset though, it did not linger for long. O'Sullivan was not at his sharpest but chances kept presenting themselves and he capitalised often enough to put daylight between himself and Page.
The 16-year-old from Ebbw Vale, whose bushy beard disguises his youth, is widely tipped for a bright future in the sport and pinched another frame but his involvement in York was unsurprisingly short-lived.
O'Sullivan, who won his first UK title aged 17 in 1993, said of Page: "I think he's a fantastic talent. That was the first time I'd ever seen him play and he's by far the best British junior I've seen.
"Some youngsters could have come out and frozen but he didn't. He's got a good temperament and a big future."
O'Sullivan said his own display had been "all right, nothing special".
Amateur Page was a late addition to the draw, replacing Scotland's Rhys Clark who pulled out for medical reasons.
The youngster said of his big-stage appearance: "I played OK. It's Ronnie though, he's different class.
"It was great to play Ronnie. I suppose I'd have taken 6-3 - you want to win but you don't want to get hammered."
Jimmy White rolled back the years with a 6-2 victory over Ali Carter.
White is ranked a lowly 115th, fully 101 places behind Carter, and the ever-popular 55-year-old needed a tour wild card in the summer to extend his career.
But the Whirlwind turned on the style, finishing off his fellow Crucible nearly man with breaks of 128 and 61 in the final two frames. While White has lost in six World Championship finals, Carter was beaten in two by O'Sullivan.
White, the 1992 UK champion, said: "These tournaments are the ones you want to excel in, the absolute big ones. I know if my game's on I can beat anybody, and I've proved that to myself."
Mark Williams saw off North Yorkshire's Paul Davison 6-0 but the Welshman, who has won this event twice, could withdraw from the tournament.
His wife, Jo, is in hospital and Williams, who won the Northern Ireland Open on Sunday, is considering forfeiting his place to return home.
Former world champions Graeme Dott and Ken Doherty were also winners on day three of the event.
Morning Session
First Round (Best of 11 frames)
- Mark Williams 6-0 Paul S Davison (Match 5)
- Andrew Higginson 6-0 Sam Craigie (Match 6)
- Mark Joyce 6-3 Thor Chuan Leong (Match 9)
- David Gilbert 6-4 Christopher Keogan (Match 10)
- Graeme Dott 6-2 Josh Boileau (Match 35)
- Liang Wenbo 6-1 Sanderson Lam (Match 37)
- Stuart Carrington 2-6 Mitchell Mann (Match 38)
- Fergal O'Brien 4-6 Akani Songsermsawad (Match 56)
Afternoon Session
First Round (Best of 11 frames)
- Gary Wilson 3-6 Ken Doherty (Match 11)
- Neil Robertson 6-1 Rod Lawler (Match 12)
- Alan McManus 6-3 Robin Hull (Match 19)
- Chris Wakelin 6-1 Lee Walker (Match 34)
- Dominic Dale 6-0 Adam Duffy (Match 36)
- Kurt Maflin 6-1 Alexander Ursenbacher (Match 43)
- Ali Carter 2-6 Jimmy White (Match 44)
- Michael Holt 6-5 Niu Zhuang (Match 55)
Evening Session
First Round (Best of 11 frames)
- Li Hang 6-1 Gerard Greene (Match 3)
- Robert Milkins 6-1 Chen Zhe (Match 4)
- Ronnie O'Sullivan 6-3 Jackson Page (Match 49)
- Alfie Burden 5-6 Michael Georgiou (Match 50)
- Barry Hawkins 6-1 Kurt Dunham (Match 53)
- Matthew Stevens 3-6 Hammad Miah (Match 54)
- Xiao Guodong 6-0 Chen Zifan (Match 61)
- Tom Ford 6-1 Eden Sharav (Match 62)
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Fast Results
Scores
