A second straight round of 6-under 66 and 12-under total has given McIlroy a two-shot buffer from a surging Bryson DeChambeau (69) heading into the final round as the Northern Irishman seeks to break free of his Masters torment and complete the career Grand Slam.

Top five on three separate occasions, Day will start Round 4 seven strokes back in a tie for sixth but conscious that momentum can change quickly on a Sunday at Augusta.

A chip-in for birdie at the par-4 14th was the highlight of Day’s third round of 1-under 71 as fellow Aussie Min Woo Lee dropped from contention with a round of 5-over 77 that included a penalty stroke when he was deemed to have made his ball move on the 13th fairway.

Day’s first birdie of Round 3 came courtesy of a clinical pitch shot to four feet at the par-5 second, his second via a curling 18-foot birdie putt at the par-4 fifth.

He scrambled pars at six, 10 and 11 but made his second bogey for the week after hitting his tee shot long and left at the par-3 12th to drop back to 5-under.

He was in a share of fifth when he holed out from the back of the 14th green but the 37-year-old dropped back to a tie for seventh when he made bogey at the par-3 16th, choosing to chip sideways from the top shelf of the green to feed his ball down to the hole location on the bottom section.

“Sundays at Augusta is unlike any other tournament. You just never know what potentially could happen,” said Day.

“I know that if you shoot a low one, you can use the crowd as momentum, and it also works against you, as well.

“He seems like he’s very focused and level-headed right now, and he’s going to be a very, very difficult person to beat tomorrow, just the way that he is looking off the golf course before the round. Very confident, very balanced in himself.

“I know it’s in the back of his mind, but I think he’s running off so much confidence and he has so much belief in his game that it almost… like he knows it’s going to happen, kind of thing.

“And when you’re playing like that, it’s very dangerous.”

Lee made a bright start to Saturday when he holed a sliding left-to-right eight-footer for birdie after almost driving the green at the 350-yard third.

He almost holed his second shot from 177 yards at the par-4 fifth but would three-putt from just inside 20 feet and make bogey.

Missed greens led to bogeys at both 10 and 11 and then Lee incurred a penalty stroke at the par-5 13th after it was assessed that his actions near the ball caused it to move in the fairway.

That resulted in a third bogey in four holes which became four in five when a wayward tee shot had the 26-year-old out of position on his way to a dropped shot on 14, his final bogey coming with a third three-putt for the day on 17.

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