Montgomerie managed just a 1-under 69 on Friday, but it was good enough to hold the lead midway through the WGC-American Express Championship, where he stands one stroke clear of the field with a two-day total of 7-under-par 133.
But Montgomerie likes the way he's playing, and he was happy with his score on a day when every player on the leaderboard's top-10 also fired rounds in red numbers.
'Anything in the 60s is a reasonable effort, and I'm glad to be in at 69,' said Montgomerie, who finished second at this year's British Open. 'My game's in good shape, but my confidence is high and that's what keeps me in good shape.'
Montgomerie has had a Hall of Fame career on the European Tour, capped by seven consecutive Order of Merit titles and seven straight Ryder Cups. But there are two glaring omissions on his golf resume: a major championship and an official win in the United States.
The latter could be taken care of this weekend if he can put together two more solid rounds at Harding Park Golf Club.
Montgomerie showed flashes of toughness with three birdies Friday, including two on par-3s. But two bogeys on the back-nine were unfortunate, especially with names like Tiger Woods, John Daly, Sergio Garcia, Angel Cabrera and Vijay Singh all within four strokes.
Still, Montgomerie probably likes his chances.
'Confidence ... comes in good shots and good putts, and that's what I've got right now,' he said.
Daly and David Howell shot matching 67s and trail Montgomerie by one stroke at 6-under-par 134. Howell came up short on a 6-foot par putt at 18 that would have given him a share of the lead.
'I'm obviously happy with my position, but I didn't swing the club particularly well today,' Howell acknowledged.
Woods, who eagled the par-4 seventh after knocking his tee shot within 6 feet, shot a 68 and leads a group of six players tied for fourth place at minus-5.
Cabrera is also there after a second-round 66, and so is Mark Calcavecchia (68), Jim Furyk (67), Fred Funk (68) and Sean O'Hair (67).
Garcia shot a 69 and is tied for 10th place with Stephen Ames (64), Billy Mayfair (67), Stuart Appleby (65) and David Toms (68). That group is in at 4 under.
Singh managed just an even-par 70 in his second round and is tied with five others for 15th place at minus-3.