Rory McIlroy feels a round in the 'mid-60s' will be required on Saturday if he is to have a realistic chance of winning the Masters and completing a career Grand Slam.
The Northern Irishman followed a battling first-round 72 with a 73 on Friday to be one over at the halfway stage - five adrift of the clubhouse lead held by Charley Hoffman and Sergio Garcia.
McIlroy - who famously led by four heading into the final round at Augusta six years ago, only to shoot 80 - suffered outrageous misfortune on the 18th, when his approach shot struck the pin and bounced off the front of the green, leading to a bogey.
Yet despite that bad break, the world number two was able to remain positive as he assessed his chances ahead of the weekend.
"I still feel like I'm right in this tournament," said McIlroy. "It was just one of those days again where you had to grind out pars and pick up birdies when you could."
Asked what he will require on Saturday, he replied: "Mid 60s. The weather's going to be better, the wind's not going to be as strong, I'm five behind at the minute and there's probably going to be a good few guys that finish ahead of me going into the weekend.
"If I can put together a 67 or a 66 tomorrow, I feel like I'll be right in there for Sunday.
"I know more than most what can happen on Sundays around here, good and bad. I shot 66 in the last round [in 2015] and I shot 80.
"So, it's just all about getting yourself in position ... but I feel like I need something in the 60s to at least to get myself in there.
"I'm not disappointed, I'm disappointed by what happened at the last, but I'm in a decent position going into the weekend.
"If I can get off to a fast start tomorrow [Saturday], a couple under through three, I'll be right there."