Sonoma, Calif. » John Cook took a six-stroke lead in a bid for his second Champions Tour victory in three weeks, shooting a 5-under 67 on Saturday in the third round of the season-ending Charles Schwab Cup Championship.

Cook, the Administaff Small Business Classic winner two weeks ago in Texas, had a 19-under 197 total on the Sonoma Golf Club course, the best 54-hole score in a 72-hole tournament since Jack Nicklaus also had a 197 total in the 1990 Senior Players Championship. Cook tournament-record 62 on Friday.

The six-stroke lead is the largest after three rounds on the Champions Tour since Jay Haas had a six-stroke lead in the 2005 Schwab Cup Championship.

Russ Cochran (68) was second at 13 under. Tom Watson (71), who began the day four shots behind Cook, and Brad Bryant (69) were 12 under.

Season points leader Loren Roberts had the day's best round with a 66 to move to 7 under.

The season points winner will receive a $1 million annuity.

Viking Classic

PGA Tour officials canceled the weather-stricken Viking Classic on Saturday because of unplayable course conditions.

There will be no makeup date and players will move on to the final event of the season, the Children's Miracle Network Classic on Nov. 12-15 in Orlando, Fla.

Annandale Golf Club received 1.75 inches of rain overnight Friday and Saturday, completely soaking an already marginal course that had areas of standing water and large tracts of mud.

Madison has received more than 20 inches of rain in the last six weeks.

"I told them this was closer to a FEMA disaster site than a golf course," tournament director Randy Watkins said. "Somebody asked if you could play somewhere else. I don't think you could play golf within 150 miles of here."

Officials postponed, then canceled play Thursday and Friday mornings after nearly constant rain. There had been hope officials might shorten the tournament to 54 holes and play next week or weekend, but groundskeepers don't think the course will dry out that quickly.