Tom Kite set a U.S. Senior Open record with a 28 on the front nine at Indianwood and finished a 5-under 65 on Thursday.
Corey Pavin's sixth birdie on his 17th hole pulled him into a tie atop the leaderboard, but a penalty pushed him back to the pack after completing his first round.
Pavin hit a chip after his ball moved back a fraction of an inch when he grounded his club on his 14th hole and that later cost him two strokes.
''Yeah, I agree,'' he said after watching slow-motion replays of the infraction with officials in a TV trailer.
That setback put Bernhard Langer and Lance Ten Broeck in second place, one shot behind Kite. It pushed Pavin into a five-way tie for fourth with Fred Funk, Jeff Sluman, Tom Pernice Jr. and Mikael Hogberg at 3-under 67.
''Still a very good score,'' Pavin said. ''I just like the way I played. That's the important thing now. There's three more rounds and lots of time to make it up and lots of golf left.''
Kite, who matched the lowest nine-hole score of his career on the front nine, is confident his window to win on the Champions Tour hasn't closed.
The 62-year-old Kite expects players like him to have success more than a decade into their career on the 50-and-over circuit because they're staying in shape and relentlessly working on their game.
''You probably haven't read, but 60 is the new 40,'' Kite said.
Kite, whose season-best finish was a tie for second four months ago at the Toshiba Classic, hasn't won on the Champions Tour was in 2008.
He put himself in a position to end the drought on the front nine with an eagle from 155 yards at the 424-yard, par-4 No. 4 with a blind shot over a hill.
''The gallery let me know it went in the hole,'' Kite said. ''So it must have run out nicely out of that semi-rough.''
Kite also had five birdies before making the turn, leaving playing partners Peter Jacobsen and Scott Simpson to marvel at his 7-under front nine.
''I felt like the Washington Generals playing against the Harlem Globetrotters out there,'' Jacobsen said. ''He didn't miss a shot on the front nine.''
Simpson said Kite played textbook golf to have his way with a course with tight fairways, thick rough and quick greens the USGA set up to be the hardest on the Champions Tour this year.
''I certainly didn't think there was a 28 out there,'' Simpson said.
Jacobsen, though, saw a breakout round coming from Kite after giving him lessons of sorts with Olin Browne recently at Pebble Beach.
''We gave him a couple ideas, and they worked last week and they obviously were still working,'' Jacobsen said. ''We all know each other's games and each other's swings, so we can tell when something is a little off and help each other out.''
Kite had the best nine-hole score in a USGA championship. There were seven 29s, including three at the U.S. Open, most recently by Vijay Singh in 2003. Olin Browne had the previous U.S. Senior Open record, shooting a 29 on the back nine in the third round last year at Inverness.
Kite scrambled to save pars on the back nine, especially when his drive at the 490-yard, par-4 12th -- perhaps the toughest hole on the course -- went left and into water. He recovered with a jaw-dropping approach from 209 yards that set him up with a 4-foot par-saving putt.
''That was probably the best shot I had all day,'' he said.
Kite's worst swing cost him a relatively comfortable cushion, heading into the second round. His tee shot at the 195-yard, par-3 17th landed in ankle-high rough on a decline to the left of the green. His flop shot went about 2 feet, leading to a double bogey that turned his three-shot lead into a one-stroke edge at the time.
''This golf course is tough enough it will bite you,'' Kite said. ''Nobody's going to play 72 holes out here without having it jump up on a hole or two and kick `em in the rear, and it got me on 17. There are just some places that, if you miss it, you're going to pay the penalty.''