Dustin Johnson began the third round of the British Open as the leader, having impressed everyone with the way he shook off that stunning loss at Chambers Bay.

Now, he's facing fresh doubts about his ability to finish off a major championship.

After squandering a day for going low, Johnson left himself with a massive catch-up job on Monday.

"I'm going to have to put together a special round to have a chance," he said. "Get off to a really good start, maybe, you never know what happens. Anything can happen."

Johnson didn't sound persuasive. Not after the way he staggered to a 3-over 75 Sunday while most of the top contenders were ripping up the Old Course, taking advantage of the soft greens and slight breezes.

There was red all over the scoreboard.

Not for Johnson, though.

He made only one birdie all day, leaving him with a 7-under 209 total that puts him five shots off the lead.

"I didn't feel like I played that bad," he said. "I just couldn't hole the putts. I felt like I was hitting good putts. They just weren't going in the hole. There's nothing you can really do about that."

After that absurd assessment, Johnson had a bit more clarity. He knew he let another prime chance slip away at a major.

"It felt like it played very easy out there," Johnson said. "Got a little tricky coming in, but the first 11 holes couldn't have played any easier."

Spraying shots and struggling with the putter, he muddled through the front nine with a 37 — the worst score posted by anyone in the final 17 twosomes. It didn't get any better on the back side, where his lone birdie at the 15th was wiped out by bogeys on the final three holes.

Johnson was the only player in the top 25 who failed to break par. Ryan Fox, with a 76, was the lone player to post a higher score in the round.

At the 18th, Johnson's frustration was complete. A booming drive left him with a little wedge to the flag. With the pin hanging near the front of the green, he cut it too close and watched the ball roll back into the Valley of Sin. His birdie putt was timid, stopping about 5 feet short. Then he pushed it by the right side of the cup, settling for another bogey.

"I felt like I was playing pretty good," insisted Johnson, who opened with a 65 and followed a 69 during a second round that stretched over two days because of weather delays. "Obviously today is the easier of the three days that we've played golf by quite a few shots. I played my worst round, and I don't feel like I played that bad. It's definitely frustrating."

This isn't the first time Johnson has faltered at a major.

There was his final-round meltdown in the 2010 U.S. Open at Pebble Beach, followed a couple of months later by his disputed two-shot penalty on the 72nd hole of the PGA Championship that cost him a spot in the playoff.

Then, of course, there was last month's U.S. Open, when he had a 12-foot putt to win the title on the final hole. He wound up three-putting, handing the trophy to Jordan Spieth.

Johnson and Spieth played together over the first two rounds in St. Andrews, and Johnson looked very much like the superior player. But Spieth, who has won the first two majors of the year, knows how to finish the job on the weekend. He was at it again on Sunday, surging within a shot of the lead with a 66, keeping alive his hopes of being the first player to win the Grand Slam.

As for Johnson, he's got 17 players ahead of him and is tied with seven more, which will make it extremely difficult to work his way back up the leaderboard.

Clearly, he's still got some work to do when it comes to finishing at a major.

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