David Frost fired a 5-under 66 on Saturday to maintain his 1-stroke lead after two rounds of the Toshiba Classic.
Frost, a two-time winner on the Champions Tour, finished 36 holes at 13-under- par 139.
Fred Couples kept pace with Frost as he also posted a 66 in round two. The 2010 champion remained one stroke off the lead at minus-12 at Newport Beach Country Club.
Jim Gallagher, Jr. managed a 3-under 68 to finish two rounds at 8-under 134.
Scott Hoch fired a 7-under 64 for the low round of the day Saturday. He jumped into a share of fourth place at minus-7. Hoch stands alongside 2007 champ Jay Haas (66), Bob Tway (67) and D.A. Weibring (68).
Couples was one back to start the round, but grabbed the lead with back-to- back birdies at two and three. He gave those two strokes back as he faltered to bogeys at the fourth and sixth.
Frost birdied the sixth from the fringe to move two clear at minus-9. Couples came back with a birdie on the seventh. Frost then tripped to a bogey on the par-3 eighth to slip back into a share of the lead.
The duo matched each other shot for shot over the next nine holes. They both birdied the 10th and 12th to get to 11-under.
Couples and Frost birdied the par-5 15th and they were two clear of Gallagher, who went on to bogey No. 17.
Frost moved back in front with an 18-foot eagle putt at the par-5 closing hole.
"It was a day where Freddie and I sort of battled it out. We were on top of the leaderboard all day and he made a nice birdie on 10 and I followed that on top of that and then again at 13," said Frost. "I think we both played steady golf. I think it will be a fun day tomorrow."
Couples only managed a birdie there to finish one back.
"I really like the course. I feel like for some reason a lot of people struggle on these greens. I do struggle at times, but very rarely with the speed of the greens and that certainly helped me today," Couples stated. "You don't want too many 4- and 5-footers for par out here if you're going to try and catch David. My goal is to go out and try to play better than I played today and continue to make a few putts."
NOTES: Frost has at least a piece of the 36-hole lead for the sixth time in his Champions Tour career ... He has won two of the previous five events, including last year's Liberty Mutual Legends of Golf with his partner Michael Allen ... Defending champion Loren Roberts managed a 1-under 70 to end two rounds tied for 22nd at 3-under-par 139.