The Glasgow cueman made a break of 118 in the opening frame at York’s Barbican Centre before Robertson produced faultless snooker to wrap up a 6-1 victory and seal a quarter-final spot.
The Australian made breaks of 126, 76, 101 and 55 before clinching it with a 113 as Maguire could only watch on from his chair.
At 3-1 behind, the Scot did have a good chance to narrow the deficit to one frame – trailing by seven points with just the colours remaining – only to see the cue ball go into the middle pocket after potting the yellow.
Robertson cleared up and went on to win without losing another frame, but the 34-year-old acknowledges it was just one of those days when he was on a hiding to nothing.
“That was a lesson,” said Maguire. “If I went back in time, there would still be nothing I could do about it – I just need to hold my hands up and say ‘well played’ because he was awesome.
“He was high and he was potting everything. There wasn’t a ball safe on the table in the end.
“The way he finished was fitting – I’m actually glad he made a century because of the way he played throughout the match.
“That yellow where I went in-off at 3-1 might not have changed things or it might have changed things, who knows, but it wasn’t to be.”
Robertson is now just three wins away from lifting the UK Championship trophy for a second time, after triumphing back in 2013.
Maguire claims the world No 3 will take some beating this week. “If he plays like that, he wins the tournament – it’s as simple as that,” added Maguire. “I wasn’t leaving him in, he was making his own chances.
“In all honesty, he’s not going to keep that up because it’s impossible, but if he keeps 90 per cent or 80 per cent of that then he’s got a right good chance.
“Obviously I was hoping to make it through because it would guarantee one Scot would be in the semi-finals but I’ll go home and have a good Christmas.”
In Thursday afternoon’s other last-16 clash, Liang Wenbo won a dramatic final frame to beat Tom Ford 6-5.
Ford had led 5-3 before Liang made breaks of 88 and 53 to force a decider and the Chinese star held his nerve to get over the line, booking a quarter-final with Marco Fu.
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