Well, if you consider a pair of closing 31s to be nice, then, yeah, it was a nice back nine.
Watson rolled in a 45-foot putt on the final hole of the day, his fifth straight birdie, to earn a share of the 54-hole lead at the Ridgewood Country Club in Paramus, N.J.
Watsons 66 was the low round of the championship, thus far. He stands at 9-under-par for the tournament, tied with Bob Gilder (70) and 36-hole leader Jim Thorpe, who birdied the last to shoot 71.
Doyle, who played with Watson on Saturday, is one shot off the lead following a 68. Doyle won this event in 1999. Bruce Fleisher, who has 13 career Senior wins but no major titles, is the next nearest competitor at 5-under-par.
Watson was six shots back of Gilder heading to the 14th hole when he hit a 6-iron to two feet. Watson then birdied the par-3 15th from six feet, curled in a 20-footer on No. 16, and pitched to three feet on the par-5 17th.
Watson, 51, is seeking his first Senior major championship. He won eight majors on the PGA Tour, but never a PGA Championship.
'Because it's the PGA, that's the PGA of America, that means a heck of a lot to me,' said Watson. 'I would very much like to win this tournament, as I would the U.S. Senior Open.'
Gilder took the outright lead by making birdie on the par-3 8th, and stayed alone at the top until missing a short birdie putt at the par-5 17th. He finished his round with a difficult chip shot out of the rough to within a foot of the cup.
Were okay, said Gilder. Were right where you want to be going into the final round.
Full-field scores from the Senior PGA Championship