The Scot, a finalist in the UK Championship before Christmas, showed both sides of his enigmatic character in a startling match which made for the third successive upset - a sequence extended to four when David Gilbert beat Mark Allen in the evening.
"It was a tough green I took on to keep the break going – but I wasn’t going out playing safe today," said Maguire of the green which effectively sealed his quarter-final place.
"If it went in, I fancied dishing up. If it didn’t, I’d be going home. I’ve played a few 5-5s and I know funny things can happen. I just went for everything and managed to win.
"I never show any emotion, but I gave it the fist there and nearly uppercut myself in the chin with that punch. It was stupid really, it’s not me. But it just shows you winning means a lot.
"It has to be one of the best comebacks of my career. I haven’t done that from 4-0 down much – I had one against Mark Williams at the UK Championship a couple of years ago. But that is right up there.
"Neil was the better player and should have put me to bed 6-1 or 6-0 after the interval. You don’t get these comebacks very often, so they’re special."
Gilbert's victory over Allen was less dramatic as he won each of the opening four frames in a one-sided win, which earned him a clash with Maguire - the player he says he looked up to when heading out onto the circuit.
First, the next pair of first-round matches take place on Tuesday, with Judd Trump seeking to avoid becoming the latest casualty when he faces Shaun Murphy, and John Higgins up against Barry Hawkins.
The quarter-final line-up will then be confirmed on Wednesday, when Jack Lisowski and Kyren Wilson go head-to-head before Mark Williams takes on Stuart Bingham.
