- Oops!Something went wrong.Please try again later.
For a while on Saturday, it looked as if Phil Mickelson was going to run away with the PGA Championship.
"Lefty" flew ahead to a massive 5-shot lead early in the third round at the Ocean Course behind five birdies in his first 10 holes of the day.
But a blunder on the back nine opened the door up for the rest of the field, and Brooks Koepka took advantage.
Koepka, who started the day just one back, will now enter the final round the same way in a group alongside Mickelson at Kiawah Island in South Carolina.
Koepka is now seeking his third PGA Championship win in four starts, while the Hall of Famer is trying to become the oldest to win a major championship. Undoubtedly, the two should make for a thrilling finish.
"I left a lot out there," Koepka said. "I've got a chance to win, so that's all I wanted to do today is not give back any shots and be there tomorrow with a chance, and I've got that."
Koepka takes advantage of Mickelson blunder
Mickelson had the perfect front nine on Saturday.
He made four birdies to drop to 4-under on the day, and then made a birdie on the 10th to claim a massive five shot lead.
In what felt like an instant, though, his lead what gone.
Mickelson bogeyed No. 12 and then doubled No. 13 after his tee shot found the water. He did par out the rest of the way to finish his day 2-under to maintain a 1-shot lead.
Koepka, on the other hand, shined on his back nine. He fired three birdies on the back and had a shot at a share of the lead, but bogeyed the last hole to close out his 2-under 70 on the day. He held a share of the lead briefly, too, after he somehow reached the par-5 16th in just two shots.
While his ball striking was much better than it was earlier in the week, Koepka was still extremely frustrated with his showing on the greens.
“I struck it really nicely, I drove it really well compared to what I did the first two days, so I got that fixed,” he told CBS. “But I definitely failed putting. I think that's probably the worst putting performance I’ve ever had.”
Mickelson, thanks to a clutch chip on the final green, will enter Sunday with a 1-shot lead but will do so alongside Koepka in the final group. Louis Oosthuizen, who entered the day tied with Mickelson, sits two back after he finished with an Even-72. Kevin Streelman then sits three back at 4-under.
Though there are plenty of people within striking distance — including Christiaan Bezuidenhout and Branden Grace at 3-under, and Bryson DeChambeau and Joaquin Niemann at 2-under — all eyes will be on that final pairing on Kiawah Island come Sunday afternoon.
"I think that because I feel or believe that I'm playing really well and I have an opportunity to contend for a major championship on Sunday and I'm having so much fun that it's easier to stay in the present and not get ahead of myself," Mickelson said. "And so I think that's a big part of [my success this week].
"I think certainly my brother has played a big part in kind of keeping me present and in the moment and not letting a couple of bad swings affect me here or there, and so I think we're having so much fun that it's easy to stay present."
More from Yahoo Sports: