Lehman, the player of the year last season on the 50-and-over tour, birdied the final hole at Hualalai Resort to match Vaughan at the top of the leaderboard.
All but five of the 41 players shot par or better on the Jack Nicklaus-designed course, the easiest layout on the tour eight of the last nine years.
Lehman had five birdies and an eagle on the 10th, playing the par-5 holes in 5 under. His eagle putt on the 10th came from 20 feet.
"The wind started to blow right about then. It started to get stronger on like the eighth, ninth, 10th holes," Lehman said. "That hole was straight downwind and I hit a good drive and a 6-iron. I had like 20 feet and hit a beautiful putt, perfect speed, right in the center.
"But it was playing more like a par 4, it's like picking up a stroke or a stroke and a quarter on the field, not one of those eagles where you pick up two."
A three-time winner last season, Lehman became the first player to be honored as the player of the year on all three PGA Tour-sanctioned tours. He won the Nationwide award in 1991 and the PGA Tour honor in 1996.
Vaughan played in the third group, missing the wind that picked up to 15 mph in the afternoon. His only bogey came on the 16th hole, but he rallied with birdies on the final two holes for his lowest score on the Champions Tour by two shots. Vaughan has limited exempt status this year and got into the tournament because of his victory in the 2008 Senior British Open.
"I'm just playing the majors and will try to Monday qualify and stuff," the former fireman said.
Roberts won the 2006 event, setting the tour's scoring record at 25 under. He has 19 straight sub-par rounds at Hualalai.
Huston played the final four holes in 3 over. He and Faxon are making their first starts in the event, which is open to champions from the last two years and major champions from the last five. Eight more players, including Pavin, received sponsor exemptions.