'If you're putting for birdie 18 times you're supposed to make something, even me,' Pate said. 'They've talked so bad about me on television about my putting, I'm starting to putt better.'
Pate made three birdies on the back nine, part of a 4-under round of 68 that put him in a group two shots back in the first round of the Champions Tour Boeing Classic.
Ray Stewart, a former PGA TOUR player who made the tournament field by shooting 70 and claiming the last automatic spot in a Monday qualifier, made four birdies on his first nine, and finished with a 6-under 66.
Stewart, a native of Abbotsford, British Columbia, playing in his first tournament since the 2006 Senior British Open, didn't bogey.
Pate, who started the week ranked 62nd in putting, hit 16 of 18 greens in regulation and putted for birdie from off the green on the other two holes. He got to 2 under with a 15-foot birdie on No. 11, then hit a wedge to 18 inches on No. 16 for a tap-in birdie.
Pate capped his day by sinking a 27-foot putt on the par-3 17th.
'These greens are tough. They have a lot of slope and there's not a flat putt out there,' Pate said. 'You have to hit the perfect speed and perfect line.'
The group at 4 under also included Gil Morgan, who is struggling through one of his worst seasons on the Champions Tour. Morgan was also bogey-free in his round.
'This has probably been my worst year to date since I started out here,' said Morgan, who has just two top-10 finishes this year and has won just once since 2004. 'I seem to be making too many mistakes this year.
'It's nice to play well again and get off to a good round.'
A number of players shared the lead at one point at the TPC at Snoqualmie Ridge.
John Harris was tied for the lead at 5 under through 12. Playing No. 4, his 13th of the day, Harris hit a tree guarding the right side of the fairway with his tee shot, and the ball dropped into a lateral hazard underneath a patch of blackberry bushes.
While playing partner Loren Roberts picked the blackberries, Harris tried to save bogey, but his 8-foot putt spun around and out. Harris dropped another shot and finished with a 2-under 70. Bruce Lietzke was also at 5 under before faltering and finishing at 2 under.
Mark O'Meara, looking for his first win on the Champions Tour, got to 4 under, but bogeyed three of his final four holes for a 1-under 71. Nick Price led a group at 2 under that also included Mark McNulty, who won The Tradition last week.
Defending champion Tom Kite rallied late, birding three holes on the back nine to finish even.