Hale Irwin, who has accomplished more on the Champions Tour than any other golfer, will attempt to become the first to defend a MasterCard Championship title in Hawai'i when the season-opening event tees off tomorrow at Hualalai Golf Club.

Irwin won by five shots last year. He separated himself from the field with a second-round 62, missing a birdie on the final hole that would have allowed him to shoot his age. It was his 45th senior championship, but first since 2005. In 2006, Irwin was winless for the first time since turning 50.

Irwin's winning score of 23-under 193 was his lowest winning score in a 54-hole event. Hualalai played to an average of 68.715 — more than 3-under par. Irwin also won at Hualalai in 1997, the first year it moved here.

The 25th MasterCard Championship at Hualalai is the first of 29 official senior events in 2008. Total prize money is $55.5 million. The 41-man field — largest in history — is made up of winners from the past two years, major champions from the last five and sponsor choices Ben Crenshaw, Curtis Strange, Lee Trevino and Lanny Wadkins.

Mark James is the only player eligible who declined the invitation. Andy Bean withdrew Tuesday because of a bad back.

Irwin, who represents Hokuli'a, tees off at 12:22 p.m. in the first round, playing with Fred Funk. That twosome will be followed by Allen Doyle and Jim Thorpe. Former Kailua resident Scott Simpson starts at 12:40 p.m.

Proceeds from this year's event benefit Rotary Club of Kona, Kealakehe High School Dance Team and Big Island Junior Golf Association. MasterCard has raised almost $500,000 for charities in the Kailua, Kona community since 1997.

The following week, Funk will defend his title at the $1.6 million Turtle Bay Championship on O'ahu's North Shore. That full field (78 players) includes all but three of last year's top 25 money winners and Isao Aoki, Kiyoshi Murota, Joe Ozaki and Hawai'i's David Ishii, Dave Eichelberger and Dick McClean. Steve Veriato, born and raised on the Big Island, is an alternate.

Golf Channel will broadcast a 1-hour Champions Tour preview show today at 2 p.m.