Rory McIlroy admitted a poor finish to the third round had left him with little chance of completing his career grand slam in the Masters at Augusta.
McIlroy was six under par for his round after 15 holes but bogeyed the 16th and 18th and had to settle for a 68 to finish six under, with 36-hole leader Jordan Spieth showing no signs of coming back to the field.
"I'm going to need something basically around 61, 62 (tomorrow) to have a real chance. I'm not sure that's going to happen but we'll see," said McIlroy, who is looking to become just the sixth player in history to win all four major titles.
"I've really just tried to treat it like a normal golf tournament or treat it like any other year. Any other year that I've came to the Masters, I've done the same things.
"I wasn't approaching it like I was trying to win the grand slam. I was approaching it like I was trying to win another golf tournament. So I don't think it's really had any impact on the way I've played this week."
McIlroy feels like his knowledge of Augusta is improving with every round, although the bogeys near the end of his Saturday effort left him feeling a little flat.
He added: "I got off to a good start, sort of the way I wanted to play the front nine.
"I had not really played the front nine too well the last couple of days, so to play them under par was nice.
"I made a couple of good birdies on 13 and 15 so got it to eight under through 15 and then a disappointing finish. Overall I felt like I played pretty well and just a little disappointed the way I finished.
"I definitely feel like I play this golf course better and better every year that I come here. I just need to keep putting numbers up like I did today. I know I'm capable of it. Just a few stretches of holes have held me back and that's really been the case this year again."