BLAINE, Minn. -- Gil Morgan was happy to shoot his age Friday, yet slightly disappointed his score wasn't even lower.
"I didn't have too many mistakes, I didn't miss many greens, but I had a few opportunities that kind of slipped away putting-wise," Morgan said.
He had a bogey-free round, but missed four putts in the 6- to 10-foot range, while making a handful of long ones, including a 40-footer for birdie on the par-3 13th.
On an ideal sunny day with a slight breeze early, 49 of 81 players shot below par at the TPC Twin Cities, where the fairways are wide and the greens soft.
"The way the course is playing it's going to be a traffic jam up at the top this year," Senior said. "Unless we get some real strong wind ... I think it's going to be 20 under to win this week or if you're going to have a chance."
Starting on the back nine, Morgan birdied five of seven holes midway through his round to put himself atop the leaderboard. It is the second time in two years that Morgan has shot his age. He had a 64 last year in the Toshiba Classic.
Anywhere near the front of the field has been an infrequent occurrence for the oft-injured Morgan, whose latest ailments include elbow surgery last year and a sore wrist now. He has only one top-25 finish in 11 starts this year, five in his last 27 overall. In his last 75 tournaments dating to 2008, his best finish is third. He won the last of his 25 Champions Tour titles in 2007 at Pebble Beach.
"The last couple of years have been strange. I've had a few injuries that have plagued me a little bit, but at the same time I haven't played very consistently. I've had some really low rounds at times, but I can't seem to put it together for three rounds," he said. "A round like this will say that, `Hey, you can still do it a little bit.' Hopefully, I can continue it at least a little bit for the rest of the week."
Senior, who tied for second last year, made four birdies in a five-hole stretch to get to 5 under, then had birdies on Nos. 6 and 7 -- on his back nine -- to move into a tie for the lead.
"I had a couple of unfocused bogeys, but all in all, I'm pretty happy with the day's play," he said. "It's always great to be up there after the first round."
Pate had his best round on the 50-and-over tour. He worked with Dave Stockton on his putting for about 20 minutes Thursday and switched from a belly putter to a traditional one this week. The 51-year-old Pate birdied five straight holes early in the round and hit every green in regulation.
"My security blanket on short putts is gone, but I made some. I made four putts outside 15 feet, I haven't done much of that," said Pate, who has finished 20th or worse in six of his past seven events. "I switched to the belly putter maybe two months ago and putted well for three weeks and then it just got awful again. Try something different."
Lu had eight birdies and a bogey.
Defending champion Jay Haas opened with a 71.