Rory McIlroy believes he still has a chance to win the Masters and complete the career grand slam after Jordan Spieth's late stumble threw the tournament wide open.
Spieth held a four-shot lead with two holes to play and was eight clear of playing partner McIlroy, who struggled to a 77 and failed to record a single birdie for the first time in 81 major championship rounds.
However, the defending champion then bogeyed the 17th and ran up a double bogey on the last to finish just a shot ahead of compatriot Smylie Kaufman, with McIlroy another four shots behind.
"I couldn't get anything going really," McIlroy said. "It felt more like a US Open than a Masters today. I am disappointed. I felt like I righted the ship a little on the back nine but couldn't take the few opportunities I gave myself.
"If I am to take heart from anything then it's the fact Jordan has just let a lot of people in after his finish. But I need to get off to a fast start tomorrow. The forecast is for better conditions and we know stranger things have happened, but I need to play a lot better than I played today.
"I think it's winnable from here. If Jordan hadn't had that finish then I would probably say no, but he finished that way and the guys on two and three over like myself feel like we have a chance now. I just have to make sure that I get off to a fast start and put some red numbers on the board and make a bit of noise to put a bit of pressure on the guys playing behind me.
"I need to be more aggressive. I played very tentatively today right from the get-go. I hit it in the bunker on two and that was the way of it. I didn't birdie any of the holes I had been doing for the first two days, I didn't take advantage of the par fives.
"I made a couple of big numbers and had no red on the card and that is never going to bode well. I was trying so hard on that last putt to just make one birdie today but it wasn't to be.
"I'm only five back and I can't believe I am standing here saying that because I was eight behind standing on the 17th tee. I need to regroup and stay positive and go out and attack tomorrow."