2021 PGA Championship leaderboard breakdown, scores: Phil Mickelson eyes history with 54-hole lead

Mickelson would become golf's oldest major winner if he closes out this PGA Championship

Moving Day at the 2021 PGA Championship lived up to its name, and the drama-filled third round on the Ocean Course at Kiawah Island has set the stage for what should be a tremendous final 18 holes on Sunday. The entire day revolved around Phil Mickelson, who at age 50 is looking to become the oldest major champion in history.

Mickelson started the day tied for the lead with Louis Oosthuizen and ended it atop the leaderboard on his own. He's just the fourth man age 50 or older to lead a field after 54 holes in major championship history. While none of the other three went on to win, and Lefty's game has not been in top form over the last few years, the fact that he was able to battle through a tough third round gives reason for optimism entering Sunday's final 18 holes.

Though the lead is a nice consolation prize for Mickelson, it's not nearly as large as it could have been. Lefty had an opportunity to lead by six midway through the round, but he was instead forced to fight through some miscues to ensure he never dropped from the top of the leaderboard. Mickelson led wire-to-wire on Saturday, though Brooks Koepka did catch and tie him at 7 under for a moment over the final few holes.

In addition to the age factor and all the potential history that brings with it, Mickelson is looking to join an exclusive club of golfers with 6+ majors. The future Hall of Famer is looking to become the 14th name on that list, joining Lee Trevino and Sir Nick Faldo. Lefty has not won the PGA Championship since 2005, and he has not captured a major since taking The Open Championship in 2013. If he gets the job done Sunday at Kiawah Island, this will be a major win for the ages. (Pun intended.)

Let's take a look at the top of the leaderboard after 54 holes at the 103rd PGA Championship.

Rick Gehman and Mark Immelman break down and react to Saturday's third round action at the PGA Championship. Follow & listen to The First Cut on Apple Podcasts and Spotify.

1. Phil Mickelson (-7): This was a Phil Mickelson round if there ever was one. Lefty was as low as 10 under for the tournament and led the field by five strokes when he had a birdie putt to increase his advantage to six. He just missed it, and less than 30 minutes later, saw his lead drop to a pair. And that's before his untimely double bogey on No. 13. Mickelson went on to see a number of other putts come an inch from falling; between those heartbreakers, he toughed it out of the sand and even recovered after dunking a ball in the drink. It looked like the elder statesman was on the verge of not only a victory but a rousing and dominant one at one of the toughest courses in the nation. Instead of a walk in the park, Sunday will be race down a treacherous highway as Lefty battles a strong top of the leaderboard for his sixth career major and first in eight years.

2. Brooks Koepka (-6): The winner of two of the last three PGA Championships, Koepka battled the wind and his surgically-repaired knee with a tremendous showing on the back nine at Kiawah Island. He pounded drives but struggled to clean up on the greens with his putter costing him an even lower score. Koepka did shoot a 34 coming in after an even-par start, but a bogey at the last took him out of a tie from the lead, which he held for over an hour late Saturday afternoon. Koepka will be the betting favorite entering Sunday's final round -- and for good reason.

3. Louis Oosthuizen (-5): Holding serve was not necessarily the worst result for Oosthuizen given that Mickelson fell back to Earth after pulling away early Saturday afternoon, but it was a missed opportunity to grab hold of a tournament by utilizing his cunning and guile. He started slow with a birdie and bogey on the front before finding the lead again momentarily at 7 under on the 12th hole. He immediately bogeyed he 13th and finished 1 over down the stretch with his putter consistently failing him. A second major championship is a legitimate possibility for the South African if he can keep his head in the game Sunday.

4. Kevin Streelman (-4): Steady was the name of the game for the American, who shot 3 under over a 14-hole stretch only to bogey the last. The 42-year-old has not finished inside the top 15 of a major since 2016, and his best-ever finish at such an event came at T12 at the 2013 PGA Championship. To say a come-from-behind wind Sunday would be a career moment for the two-time PGA Tour winner would be an understatement.

T5. Christiaan Bezuidenhout, Branden Grace (-3): A strong effort on the back nine put Bezuidenhout in contention as he registered three birdies on the Ocean Course's toughest stretch. Though he has three European Tour wins and is ranked No. 33 in the Official World Golf Rankings, Bezuidenhout has yet to win on the PGA Tour and has never finished better than T38 at his five major appearances since 2019. Grace was as low as 5 under at the turn, but a 38 on the back nine put him in a tougher position than he should've seen entering Sunday.

T7. Bryson DeChambeau, Joaquin Niemann, Gary Woodland (-2): DeChambeau's round would've looked much better had it not been for a double bogey on No. 17 that spoiled a to-that-point stretch of 12 holes without the Big Golfer striking a negative number. Instead, an otherwise strong day ended with a 71. Woodland similarly ruined a strong round with double bogeys; the difference is that he picked up three of them surrounded by six birdies to finish with a 72. Both men, who are looking for their second career majors, sit five back of the leaders, which is a difficult number to make up at this course.

T13. Jordan Spieth, Rickie Fowler, Tony Finau, Patrick Cantlay and six others (E): Though they are not in contention to win, these four put together stellar efforts Saturday. Spieth and Fowler were both seven shots better than their Friday rounds. Spieth posted a 4-under 68 that saw him go 16 holes without a bogey, while Fowler (only playing the PGA Championship on an exemption) put up a 69 with a 13-hole bogey-free streak before the 18th caught him. Finau and Cantlay both shot 2 under for the day and were two of nine golfers who shot under par among the top 22 on the leaderboard.

Watch Round 4 of the PGA Championship streaming live Sunday beginning at 1 p.m. ET on CBSSports.com, the CBS Sports App and Paramount+. CBS Sports updated this story with scores and highlights from Round 3 below. Check out the scores at the top of this story, a more detailed leaderboard and our complete viewer's guide for Round 4.

[May 22, 2021 at 7:18 pm ET · Kyle Porter]

Phil makes par at the last to get in at -7. Up one on Brooks. Buddy, I'm jacked.

[May 22, 2021 at 7:04 pm ET · Kyle Porter]

Brooks bogeys the last to shoot 70 and finish at -6. Phil needs to make par at the last to get in the house at -7.

[May 22, 2021 at 6:51 pm ET · Kyle Porter]

I can't believe we get to do this all over again tomorrow.

[May 22, 2021 at 6:48 pm ET · Kyle Porter]

Phil kills the hole at No. 17 for birdie, makes par and remains tied with Brooks with two holes left. Brooks made a nice putt on No. 17 for par. Both at -7.

[May 22, 2021 at 6:35 pm ET · Kyle Porter]

Phil's ball was under a golf cart tire (which was actually a good thing), and Brooks just tied the lead at -7. Phil hit an amazing shot off the beach and still has a shot at making birdie.