PORT ST. LUCIE, Fla. (AP) _ New York Mets first baseman Keith Hernandez, out for seven weeks with a broken kneecap, went 1-for-3 with the St. Lucie Mets' in the first game of a rehabilitation assignment.

Hernandez started at first base Friday night and hit third in St. Lucie's 5-3 loss to the Sarasota White Sox before leaving the game after the sixth inning. It was his first appearance since he was injured on May 17 in a collision with Dave Anderson of the Dodgers.

Hernandez hopes to rejoin the Mets next week in Atlanta.

''I'm here for a purpose and I've enjoyed my time here,'' Hernandez said. ''It's the right thing to do. Better safe than sorry.''

The five-time National League All-Star will play four games for St. Lucie. He said he expects to be in the starting lineup for New York Thursday night. A career .300 hitter, Hernandez was hitting .282 with three homers and 12 RBIs when he was injured.

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WIMBLEDON, England (AP) - John Parry, a former Royal Air Force parachutist, will be in the umpire's chair for the Wimbledon men's final on Sunday.

Parry, an ex-squadron leader with more than 1,000 free-fall parachute jumps to his credit, umpired the women's singles final in 1987 and the men's doubles final last year.

Saturday's women's championship will be handled by Gerry Armstrong, a full- time umpire for the Men's Tennis Council, who umpired the men's final last year.

Armstrong was the first professional umpire to work a men's singles final at Wimbledon and the first son to follow a father into the top umpire's chair. His father, George Armstrong, oversaw Arthur Ashe's victory over Jimmy Connors in 1975.

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HUNTSVILLE, Ala. (AP) - Jose Canseco, last year's American League MVP, will fly back to Oakland on Sunday, returning to the original date for the end of his rehabilitation stay with Huntsville.

Canseco, playing with the Athletics' Class AA farm team while rehabilitating his injured left wrist, was not in the starting lineup Friday night.

''He said it was sore,'' Stars manager Jeff Newman said.

Earlier Friday, Huntsville general manager Bill McKay said that Canseco had a ticket to fly back to Oakland on Saturday afternoon. But the Oakland outfielder is now apparantly leaving a day later.

''He'll be here tomorrow, and as far as I know, he'll play,'' Huntsville manager Jeff Newman said. ''I think he's leaving on Sunday.''

Canseco was voted as a starter to the American League All-Star team, but said was told Thursday by Athletics' manager Tony La Russa that he would not play.

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CORNWELLS HEIGHTS, Pa. (AP) - Philadelphia Park race track was sold for $63 million to a corporation formed by former executives for a British horse racing and off-track betting business, the track's owners announced.

International Thoroughbred Breeders Inc. said it sold the former Keystone Race Track Friday to the newly formed Greenwood Racing Inc.

International Thoroughbred said the sale is subject to various conditions, including Greenwood arranging for financing of the purchase price and obtaining a license within six months from the Pennsylvania Horse Racing Commission.

Greenwood, newly incorporated in Delaware, was formed by Bob Green and Bill Hogwood. Until recently, Green was chairman, chief executive officer and Hogwood managing director of the William Hill Organization, one of Great Britain's leading bookmaking firms.