Fred Funk shot a 4-under 67 to maintain a one-stroke lead on Saturday at the AT&T Champion-ship, his third event on the Champions Tour.
"It's great to have a lead, but I was hoping for some separation," said Funk, a seven-time winner on the US PGA Tour.
"I could have shot lower out there. I really was hoping for 12 under. But I'm playing well and I'm comfortable," he said.
The 50-year-old Funk had a 10-under 132 total on the Oak Hills Country Club course.
Raymond Floyd (66) was a stroke back and defending champion Jay Haas (64) was two shots behind along with Keith Fergus (67) and Scott Simpson (68).
Haas, coming off a victory in the rain-shortened Administaff Small Business Classic, birdied his first four holes.
Tied with Loren Roberts for the tour lead with four wins, Haas also won the US PGA Tour's Texas Open in 1982 and 1993 at Oak Hills.
When Haas won last year, he started the final round two strokes off the lead.
R.W. Eaks (69), James Mason (67), Ron Streck (66) and Jim Thorpe (66) were three shots back at 7 under.
The 64-year-old Floyd hasn't won a full-field tournament in more than six years. Despite the long drought, he wasn't not surprised with his play through two rounds.
"I came here and had eight birdies in the Pro-Am," he said.
It looked like a big day was in store for Funk. He rammed home a 20-foot birdie putt on the first hole but went five holes before he had another one.
On the back nine, his birdie at the par-5 15th was a two-putt.
He hasn't bogeyed a hole during the tournament. Still, he's not satisfied with his work on the greens.
He had 28 putts on Saturday, but Floyd had 24 and Haas 26.
"Seems like I let some opportunities go out there," Funk said. "I've got to be more aggressive on the greens."
Funk tied for 11th in his two previous starts on the 50-and-over tour, the US Senior Open and Senior Players Championship in July.
He also had a runner-up finish in April in the US PGA Tour's Zurich Classic.
Haas' fast start included an easy one at No. 3. He hit an 8-iron a foot away from the cup on the 456-yard hole.
"I just felt like at that point I could birdie every hole almost," he said.
"All of a sudden I looked up at the scoreboard and I was one out of the lead," Haas said.
Playing earlier in the day, he had three more birdies through the rest of the round. He pulled into a three-way tie for the lead with Funk and Floyd when he hit a wedge 13 feet away from the cup and birdied No. 17.
But Floyd also birdied 17, while Funk had two birdies on the back nine.
"I was kind of in a position today where a 68 or 69 wouldn't do much damage," Haas said.
Roberts was four strokes back after a pair of 68s.