AUGUSTA, Ga. — Through 36 holes, Phil Mickelson is in position to win his fourth Masters, which would tie his idol, Arnold Palmer, for four green jackets.

Mickelson is 5-under, four shots behind the leaders at 9-under, but he believes he should be in much better position entering the weekend — if not for his balky putter.

“I’m striking the ball exceptional, and I’m putting horrific,’’ Mickelson said Friday. “If I get that fixed this weekend, I’m going to make a run. I’m very frustrated and disappointed with the way I’ve putted. I’ve let eight, nine, 10 shots on the green, and it’s pathetic. I’m going to fix that and hopefully make a run.

“You can’t make those mistakes, give those shots up in this field, in this competition. But we’ve got 36 more holes, and I’m playing well enough. I struck it well enough to keep me in it despite probably being last in the field in putting. But I’m going to get that fixed for [Saturday’s] round.’’

Mickelson, who’s 50 and has struggled of late on the PGA Tour, has won the two Champions Tour events he’s played recently. Always in pursuit of hitting the ball longer, Mickelson put a 47-inch driver in his bag for this week (the average on Tour is about 45 inches).

Asked how he feels he’s driving the ball, Mickelson was not bashful.

“Awesome,’’ he said. “I’m driving like a stallion.’’

Asked for examples, he said, “I’m driving it over the trees on [number] 9 all the way down to the bottom, hitting wedge into 17, wedge into 14, 5-iron both days into [number] 2. I mean, I’m driving the ball very well. I’m hitting the ball great, and I’m putting awful. I’ve been putting well this year, and if I get this fixed for the weekend, I’m going to make a run.’’

Asked what his plans were to fix his putting, which produced several lip-outs on short par putts on Friday, Mickelson said, “I’m going to go get on a Quintic system right now and see if it’s alignment or stroke or path or what.’’

Stay tuned. If he gets the putting fixed, it could be an epic weekend. Jack Nicklaus is the oldest player ever to win a Masters, winning in 1986 at age 46. Mickelson is four years older than that and still feeling as frisky as a “stallion.’’