Jordan Spieth and Rory McIlroy were battling the elements as much as each other as they looked to create their own slice of history at Augusta National.
Spieth is looking to become only the fourth player after Jack Nicklaus, Nick Faldo and Tiger Woods to win back-to-back Masters titles, while a first green jacket for McIlroy would make him the sixth player to complete the career grand slam.
McIlroy has a weekend scoring average at Augusta of 68.5 in the last two years, but that was certain to rise due to winds gusting up to 30 mph which meant only seven players were under par midway through the third round.
Spieth, who had become the first player in tournament history to hold the outright lead after six consecutive rounds despite a 74 on Friday, began the day with a one-shot lead into the round and edged further in front thanks to a two-putt birdie on the par-five second, where McIlroy missed from eight feet having being forced to lay up from a fairway bunker.
It looked as though Spieth would give the shot straight back when he drove wildly into the trees on the third, but he punched out to the back of the green and got up and down for par, and instead it was McIlroy who bogeyed after his approach from a fairway bunker span back off the green and he failed to get up and down.
McIlroy sensed a great chance for a two-shot swing on the seventh with Spieth struggling to make par after driving into the trees and finding sand with his approach, but the Northern Irishman three-putted from 25 feet and saw his playing partner scramble a matching five.
Spieth was nowhere near the form which saw him set records for the most birdies (28) and lowest 36 and 54-hole totals last year, but was grinding out a score and birdied the eighth after pitching to four feet.
McIlroy had found another fairway bunker off the tee and had to settle for par to fall four behind, one shot behind Japan's Hideki Matsuyama and in a tie for third with 58-year-old double Masters champion Bernhard Langer, world number one Jason Day, Soren Kjeldsen and Scott Piercy.
Langer, who won his first green jacket 31 years ago, had carded three birdies and two bogeys to cover the front nine in 35, a score matched by playing partner Day to leave both men on level par.
Both then bogeyed the 12th but bounced back immediately with birdies on the 13th and 14th, where Day holed from 65 feet, to join McIlroy on one under par.
Former Open champion Louis Oosthuizen had earlier shown what was possible despite "brutal" conditions.
Oosthuizen, who lost a play-off to Bubba Watson at Augusta National in 2012, began the day in a tie for 47th after making the halfway cut with just a shot to spare.
But after defying the testing conditions caused by winds gusting up to 30mph to card a third round of 71, the South African was into a tie for 22nd as the final group of Jordan Spieth and Rory McIlroy got under way.
"It probably feels like 66," Oosthuizen said of a round containing four birdies and three bogeys. "It was a grind. There wasn't one easy shot I had today, not even having a little wedge or sand wedge in.
"I think the seventh hole is proving that. I had lob wedge in and made a good putt for bogey. So, it's just tough. It's really brutal out there.
"Coming in I told myself to really stick in there and try and squeeze level par. One or two under would be great knowing that the golf course is going to play that tough.
"If you can get the lead down to being six behind maybe, five behind, it would be great going into tomorrow. Obviously, Rory and Jordan are great players, so it will be interesting to see how they go today. But the golf course is really playing tough. I think the way it is now, a good score is probably 74, 75."
