Fred Couples and Mike Donald shook off several challenges over yesterday's final l8 holes to win the $1 million Sazale Golf Classic best ball championship in Wellington, Fla., by four strokes.

They earned $90,000 each with this first tournament triumph for Donald since July 1989 and third this year for Couples.

Starting the day with a four-shot lead, Couples and Donald scored 34-32 -- 66 at par-72 Binks Forest Country Club. They grabbed the title with 34-under-par 254 on daily productions of 65-60-63-66.

Runners-up at 258 were the Byrum brothers, Curt and Tom.

South Africa: David Frost sank an eight-foot birdie putt on the final hole in Sun City in his native land and won the 10-man Million Dollar Challenge for the second consecutive year. His prize this time: the richest in golf -- $1 million.

Frost birdied the final two holes, thanks to sparkling approach shots, to complete his fourth straight round of 1-under-par 71 and hold off by 284-285 Spain's Jose-Maria Olazabal, who closed with a 69.

LPGA: Betsy King pulled ahead with a birdie on the 15th hole and took advantage of Deb Richard's few mistakes to win the LPGA World Match Play Championship in Princeville, Kauai, Hawaii.

King was 1 up going to the 18th hole. Richard's approach landed in a water hazard and she conceded after King made the green and was left with a 20-foot eagle putt. King won $100,000, Richard $70,000.

King has been dominant on the Princeville Makai course. She also won the 1988 and 1989 Women's Kemper Opens there.

Seniors: Bob Charles shot par 70 in wind and rain to pull away from Lee Trevino and George Archer and win the Kaanapali (Hawaii) Classic. His 54-hole 206 won by four shots and paid him $67,500.

Australia: New Zealander Greg Turner shot 2-under-par 69 in wind and rain to pass Ian Baker-Finch and win the Johnnie Walker Classic in Melbourne by four strokes with 276. He earned $156,000.