Fresh from his captaincy of the U.S. Ryder Cup team, the 50-year-old Pavin is seeking his first victory on the Champions Tour.
He said he did not touch a club for 45 days leading up to the recent Ryder Cup matches, but it did not take long for him to regain his form.
"I am hitting it more solidly than I have in a long time," Pavin said.
Mark Wiebe birdied his final hole at The Woodlands Country Club to finish alone in second at 67. Another two shots back was Russ Cochran while Loren Roberts and Jay Haas were among the 10 players tied for fourth at 70.
Kenny Perry and Steve Lowery both struggled in their Champions Tour debut. Lowery had a 75 and Perry a 78. Leading money winner Bernhard Langer had his second-worst score of the year -- a 7-over 79.