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...