SAN FRANCISCO -- Kenny Perry will be rooting like heck for Fred Couples to close the deal in Sunday's final round of the Charles Schwab Cup Championship at TPC Harding Park.

Couples holds a commanding five-stroke lead over Mark O'Meara after shooting a 3-under 68 on Saturday for a three-round total of 15-under 198.

If Couples gets his first win of the season in the climactic event, Perry would claim the season points title and a $1 million annuity.

The only way Perry can lose the title is if Bernhard Langer of Germany wins and Perry finishes tied for fifth or worse in the field of 30. In fact, if anyone other than Langer wins on Sunday, Perry is celebrating.

"Well, I said I had 29 against one this week," said Perry, who shot a 4-under 67 on Saturday and is tied for seventh with Langer and Rocco Mediate.

"If Freddy can somehow make a couple more birdies and really build a substantial lead, it's really going to take a lot of pressure off me. I still need figure out a way to go out and do my own deal. I'd like to somehow top-five it and automatically win the title based on my play."

The wind is expected to kick up Sunday after three calm days, although Saturday's conditions were overcast and a bit chillier.

Couples, the biggest draw here, has been overpowering the course and the field. After back-to-back 65s in the first two rounds, Couples rallied with birdies for the third straight day on the par-5 ninth and 10th holes.

He is seeking his first win on the Champions Tour in 15 tries this year, and the noted front-runner plans to stay aggressive.

"I have a big lead," said Couples, who's finished second four times this season. "Personally, it's way better to have a five-shot lead than a one-shot lead, but this is a good course. I enjoy playing it. I really feel like the worst that I could have shot today is what I shot."

Couples and his partner on Saturday, Peter Senior of Australia, both got off to shaky starts with bogeys on the first hole. Senior is tied for third with Tom Lehman, who had the day's best round with a 65, and Bart Bryant, all six back at 204.

Couples was irritated that he three-putted from 50 feet on the first hole after mis-hitting a sandwedge.

"But I worked my way around and got it under par and made a great par on 18," Couples said. "There's a lot of shots you want to save and that was one of them."

O'Meara was pleased with his 4-under 67 that included five birdies and a bogey on 17.

O'Meara and Couples, who will be paired for the second time this week on Sunday, have a friendship that dates to the first leg of PGA Tour Qualifying School in 1980.

O'Meara said Couples will be hard to beat with his "power and his length."

"We go way back," O'Meara said. "I played with him in the final round of the Masters in '98 when I won and beat Fred. Fred will be tough tomorrow."

Of course, Perry, who has three wins this year, will be part pro golfer and part cheerleader Sunday -- just like he was Saturday morning when he urged players not named Langer to excel.

"I went around shaking all of their hands and saying, 'Come on, I need a good round out of you guys today,' " Perry said. "I was being the mayor of San Francisco."

Couples, 54, agreed that he missed a lot of putts Saturday. He said he needed to make a quality effort on the ninth, when he drained an 8-footer after leaving a 60-footer well short. He'd previously missed the hole entirely on a 4-footer on No. 7 and had another putt lip out.

"So that was a big putt on nine, and I went on and made another one, a little 5-to-6-footer on 10, too," he said.

O'Meara undoubtedly hopes for better etiquette from spectators Sunday than was exhibited on Friday when he was paired with Couples.

"I understand Fred's a fan favorite, I understand that," O'Meara said sourly. "I have no problem with that because Fred's a hell of a player. But after he putts out, when it's my turn to finish, it would be nice if people would stand still when I putt."

He added, "You'll be able to see Fred, don't worry. You'll be able to take a picture of Fred, it's all OK. When it's my turn to putt, just stand still, that's all."