OLYMPIA FIELDS, Ill. — Dustin Johnson is 21 shots worse to par than he was a week ago and still looks to be the player to beat.
Johnson and Hideki Matsuyama survived another demanding day at Olympia Fields, both scratching out a 1-under 69 that felt better than it looked to share the lead Saturday at the BMW Championship.
Everyone else was over par going into the final round.
Sunday is one last chance for some players to be among the top 30 who advance to the FedEx Cup finale, and one last round for others - like Tiger Woods - to prepare for the U.S. Open on a course that plays every bit as tough.
Patrick Cantlay only hit five fairways and didn't make a birdie as he tumbled out of a tie for the lead with a round with a 75 that left him five shots behind and might cost him a spot in the Tour Championship.
Rory McIlroy had to play left-handed to escape the base of a tree in starting the back nine with a bogey, and he finished with a shot he thought was going to be long, came up 70 feet short and led to a three-putt bogey for a 73. He still was only three shots back.
Jon Rahm matched the low round of the day at 66 that could have easily been one shot better if not for a blunder that even he couldn't believe. He forgot to set a marker down on the green before picking up his golf ball on No. 5, freezing in his tracks when he realized what happened.
''I was thinking of somebody else or something else ... and yeah, I just picked up the ball without marking it, simple as that,'' Rahm said after a round that left him only three behind. ''I can't really give you an explanation. It's one of those things that happen in golf. Never thought it would in my professional career, but here we are.''
The BMW Championship remains up for grabs, and if Sunday holds to form, it will be more about holding on than pulling away. Eleven players were separated by three shots.
Johnson and Matsuyama were at 1-under 209.
A week ago at The Northern Trust on a rain-softened course with little wind, Johnson was at 22-under par through three rounds and had a five-shot lead. That felt easy. This does not.
Johnson had a three-shot swing go against him on the opening hole when he went rough to rough to bunker and made bogey, while Matsuyama holed a bunker shot for eagle. Matsuyama quickly built a three-shot lead with a birdie on No. 4. He made only one birdie the rest of the way.
Joaquin Niemann had a 68 and was part of the group at 1-over 211 that included Adam Scott (70) and Mackenzie Hughes (69). Another shot back were the likes of Rahm, Bubba Watson, Brendon Todd and Kevin Kisner, who had 16 pars, one birdie and bogey for his round of 70.
Rounds like that go a long way at Olympia Fields, the former U.S. Open course playing like one with its thick rough and rock-hard greens and enough wind to make the fairways look tighter than they are.
Woods, meanwhile, had a reasonable start to his round and wasn't losing much ground until he lost a tee shot into the water right of the 17th fairway and then smothered a fairway metal to the left. He walked across a cart path smacking the club off the concrete and twice looked like he wanted to break it. He missed a short putt for triple bogey and shot 72.
Woods has yet to break par this week. One more round like that and it will be the first time in 10 years - the Bridgestone Invitational at Firestone - that he had all four rounds over par. He needed something around fourth to advance to the Tour Championship for the first time since 2018.
Matsuyama is trying to end three years without a victory. Johnson is trying to win for the second time in seven days, along with positioning himself to be the top seed at the Tour Championship, which would allow him to start the tournament with a two-shot lead under the staggered start.
For players like Niemann, Hughes and Scott, they are simply trying to get to East Lake in Atlanta. All of them are one round away on a golf course where small mistakes can lead to bogeys or worse on just about every hole.