Perry shot a 5-under 66 at the Bellerive Golf Club to tie Russ Cochran at the top at 7-under 135. This is the 74th playing of the oldest event in senior golf and it is also the first major tournament on the Champions Tour this year.
Perry won five times in the 2 1/2 years before he turned 50, but has had just two victories since joining the senior set. His progress has been slowed by knee problems that required surgery earlier this year.
Cochran, winner of the 2011 U.S. Senior Open, also had a 66 and the matching scores of the co-leaders were the lowest of the day.
Tom Watson stayed in contention to win at the age of 63 by turning in an even-par 71 that put him in a tie for ninth at 140.
Watson is the only player among the first 36 on the leaderboard who won a major title during his regular PGA Tour career. Watson won the British Open five times, the Masters twice and the U.S. Open once. He has captured the Senior PGA Championship on two occasions.