Naples, FL (SportsNetwork.com) - Colin Montgomerie birdied the last hole to shoot his second straight 6-under 66 in Saturday's second round and he heads into the final day with a 1-shot lead over Lee Janzen at the ACE Group Classic.

Montgomerie, who also held the first-round lead, finished 36 holes at 12- under-par 132. A 31-time winner on the European Tour in his career, Montgomerie is seeking is third victory on the Champions Tour. His first two wins came last season at the Senior PGA Championship and the U.S. Senior Open.

"If I do what I'm doing and post a good number, you never know," Montgomerie said about his chances heading into the final round. "But it's a battle, the battle commences and I really look forward to it. This is what you do this for, this is what you do this for, to get into contention on Saturday night and to see what happens."

Janzen had a great day and held a share of the lead until Montgomerie's birdie on 18. Janzen fired a 7-under 65 on the Talon Course at The TwinEagles Club and he enters the final round one shot back at 11-under 133.

Esteban Toledo and Scott Dunlap shot matching, 5-under 67s and they are tied for third at 8-under 136, four shots back of the leader.

Defending champion Kirk Triplett, who started the day two shots behind Montgomerie, settled for an even-par 72 and he is tied for 15th at minus-4.

After going bogey-free in the first round, Montgomerie picked up right where he left off at the start of day two. The 51-year-old from Scotland made a par at the first before making a pair of birdies on two and three.

Following two pars on four and five, Montgomerie drained back-to-back gains again on six and seven, getting him to minus-4 on the day and 10-under for the week, putting him up by three shots.

Montgomerie's first blemish of the week came on No. 9, where he tripped to a double-bogey, dropping him back to minus-8 and his lead was down to one. Montgomerie made the turn and poured in a trio of pars from 10 before getting back on track with a birdie on 13.

Later on, gains on 15 and 17 had Montgomerie even with Janzen, but Montgomerie stuck his approach on 18 close and he knocked that in for birdie to take the outright lead at the end of round two.

"It was good for me to finish birdie-birdie there," said Montgomerie. "I went around the turn, it was bad. I missed a very short putt on the fifth for a birdie and I missed a very short putt for a bogey on the ninth and then missed a shorter one for a birdie at the 10th. So around about the turn it was going a bit silly and then I got it back."

Janzen exploded out of the gate with three straight birdies from No. 1. Janzen later made his fourth birdie on No. 6, but a double-bogey on seven dropped him back to 2-under on the day and minus-6 for the week.

Janzen responded two holes later with a birdie on nine and he made the turn at minus-3. A pair of pars on 10 and 11 preceded back-to-back birdies on 12 and 13, tying Janzen for the lead with Montgomerie.

While Montgomerie made his birdie on 15, Janzen knocked in a gain of his own on No. 16. Like Montgomerie, Janzen made birdie on 17 and he was able to save par from a tough spot on 18 to finish just one shot back.

NOTES: Montgomerie finished tied for fifth at the season-opening Mitsubishi Electric Championship, but he ended tied for 59th at last week's Allianz Championship ... Janzen, who has missed the cut in two events on the PGA Tour this season to go along with a tie for 39th at the Allianz Championship, has never won on the Champions Tour ... Janzen has eight career wins on the PGA Tour, including two U.S. Open championships (1993, 1998) ... Kevin Sutherland made his second shot from 245 yards on the par-5 third hole for an albatross. Bart Bryant also made a double-eagle at last week's Allianz Championship.