TROON, Scotland — Henrik Stenson and Phil Mickelson delivered what everyone expects out of a major championship Saturday.
They matched birdies and improbable par saves. Momentum could change with any shot. The lead changed four times over four hours of golf at its highest level, played in the cold wind and occasional rain off the Irish Sea. All the British Open lacked Saturday was a winner.
Turns out the third round was only a preview of a duel at Royal Troon.
Stenson took the lead for the last time with another two-shot swing on an inward par 3 at No. 17, and he kept it with a nifty up-and-down on the 18th for par and 3-under 68, the second straight day no one had a better score.
That gave the 40-year-old Swede his first lead in a major at 12-under 201, even if it was just one shot over someone who has five majors and his name on the claret jug.
Stenson also set the 54-round scoring record for a British Open at Royal Troon, one better than fellow Swede Jesper Parnevik's 202 in 1997.
"There's only one thing that matters (today)," Stenson said. "I know (Mickelson is) not going to back down, and I'm certainly going to try to not back down, either. So it should be an exciting afternoon.
"I've worked hard these first three days to put myself in this situation, and I'm going to try my hardest (today) to finish the job."
Links golf can deliver some strange finishes, though this had all the trappings of a two-man race today.
Stenson had his third straight round in the 60s; he was the only player who could claim that. He is trying to become the eighth player dating to Old Tom Morris in 1861 to win his first major after turning 40. Only one player has claimed his first career major at 40-plus since 2000, Darren Clarke in 2011 at the British Open at 42.
Mickelson, winless since he lifted golf's oldest trophy at Muirfield three years ago, had 70; when Mickelson won in 2013, he nipped Stenson with a furious finish. Mickelson's game was nowhere near as sharp Saturday as his opening-round 63 that tied a major championship record for a round. Even so, he came up with the right shots at the right time until Stenson passed him late in the afternoon.
"Some days it's easy and it looks pretty, like the first couple (rounds)," Mickelson said. "Some days it's hard and it looks terrible, like it did (Saturday). But either way, I shot three rounds under par."
Everyone else felt like mere spectators.
Bill Haas, a seven-time winner on the PGA Tour who is rarely heard from at majors, was solid with 69 and alone in third at 6 under. It was his highest position in a major. Another shot back was Andrew Johnston, the Englishman with a big belly and beard to match who goes by "Beef." He broke par for the third straight day with 70.
It was unlikely to matter.
This was all about Stenson and Mickelson, two powerful players with different styles and different credentials, mainly the number of majors. Mickelson, 46, spoke earlier in the week about not having as much pressure knowing he already has won them.
Not since Davis Love and Justin Leonard shared the lead and were seven shots clear of the field in the 1997 PGA Championship had the final round of a major took on the appearance of match play.
"I've always been of the thought that it's better to be one ahead than one behind," Stenson said, "because that means Phil's got to play better than I do."
ESPN and the Golf Channel contributed to this report.