Mark Calcavecchia surrendered a three-shot cushion and finished the third round of the Senior British Open on Saturday tied for the lead with fellow American Russ Cochran and South Africa's David Frost.
Calcavecchia, the co-leader after the first and second rounds at Walton Heath, was in cruise control at 10 under with six holes to go before imploding when his accuracy off the tee deserted him.
A triple-bogey 7 at No. 13 — after driving into the heather beside the fairway — was followed by another dropped shot on No. 16, although the 1989 British Open champion salvaged something from his round with a birdie at the final hole.
Calcavecchia, bidding to become the fourth player to capture the British Open double, shot 72 to put him at 7-under 209. His stumble gave the field renewed hope in the Champions Tour's third major of the year.
Frost shot a bogey-free 66, tied for lowest round of the week on the parkland course just south of London, while Cochran's 67 included a double-bogey 6 on No. 14.
Corey Pavin, the United States' 2010 Ryder Cup captain, and England's Barry Lane each shot 69 and were a shot off the lead, with three more Americans — Chip Beck, Mike Goodes and Lee Rinker — at 5 under.
Three-time winner Tom Watson was one of four players a further stroke behind after a 69 in a third round played in overcast conditions.
Frost's 66 matched that of England's Kevin Spurgeon on Friday.
Rinker (74) and Canada's Rod Spittle (75) shared the overnight lead but couldn't maintain their form, although they are two of 12 players within three shots of the lead.
Eight of those are Americans, including Watson.
Van Pelt takes lead at Canadian Open
Bo Van Pelt birdied four of his last five holes, including the final two, to finish with 65 and a one stroke lead after three rounds at the RBC Canadian Open.
Canadian Adam Hadwin, playing on a sponsor's exemption, missed a 12-foot birdie putt on 18 to finish with a 68 and alone in second at 4-under 206.
Andres Romero (67) and first-round leader Kris Blanks (69) are tied for third, two shots back, after another tough day in the thick rough along the tight, tree-lined Shaugnessy Golf and Country Club.
John Daly, who four-putted No. 18 for triple-bogey Friday, shot 67 and is in a group of four at 2 under with Sean O'Hair (66), Aron Price (69), and Geoff Ogilvy (70) heading into today's final round.
Meanwhile, a case of vandalism on one of the greens didn't affect third-round play.
Grounds crews discovered bleach had been poured on the grass on the eighth green, a par-3 hole.
The damage was discovered at around 6 a.m. when superintendent Rob Barr was inspecting the course. Some brown spots could be seen on the green, but it didn't affect play in the $5.2 million tournament.
LPGA: Former champion Ai Miyazato of Japan shot a 5-under 67 to take a two-shot lead after the third round at the Evian Masters.
Miyazato, who won her first LPGA title at the Evian Masters two years ago, made five birdies for a 13-under total of 203.
She heads into today's fourth round ahead of a group of four players, including Kraft Nabisco winner Stacy Lewis.
PGA EUROPEAN: Alexander Noren of Sweden shot a course-record 9-under 63 to extend his lead to 11 shots after the third round of the Nordea Masters.
Noren held a three-shot overnight lead and made seven birdies and an eagle in a flawless round on the Bro Hof Slott course for a 20-under total of 196. He equaled the second-largest third-round lead ever on the European Tour, behind Retief Goosen's 13-shot edge at the 2002 Johnnie Walker Classic.
Bubba Watson shot a 69 to sit in second place.