Monty has rediscovered his old form

The Scot eagled the 16th hole and birdied the 17th to reach 13 under par, two ahead of American trio Tiger Woods, Jim Furyk and Jay Haas.

"There are four guys within two shots and that's nothing around here," said Montgomerie. "It's all on tomorrow."

Miguel Angel Jimenez and Padraig Harrington are three and four adrift.

World number one Vijay Singh posted a 68 but is still 11 shots off the lead.

I usually watch Tiger's putting but I stopped watching after the fourth hole Colin Montgomerie

Montgomerie has never won a professional stroke-play title in the United States.

While this event, hosted by Woods, is not a US PGA Tour event, it would be a breakthrough victory for the 41-year-old if he prevails over the elite 16-man field.

"It's obviously a big mistake he (Woods) invited me at all," Montgomerie said with a smile. "To get some California sun on your back in December from where I come from, it's a joy."

Woods began with a bogey, took a double bogey at the third and lipped out a par putt at the fourth, falling back to third before rallying on the back nine.

"I usually watch Tiger's putting but this time I stopped watching after the fourth hole," Montgomerie added.

The Scot finished runner-up at the 1995 PGA Championship and 1997 US Open and was joint second at the 1994 US Open and 1996 Players Championship.

His only previous victories on US soil have come in the 2000 Skins Game and the 1998 Match-Play before it became a World Golf Championships event.