ST. PETERSBURG, Fla. (AP) _ Miami running back Leonard Conley scored on a 3-yard run to lead a team of Division I-A all-stars a 21-14 victory Sunday over their I-AA counterparts in the All-America Classic game.

The I-A team also scored on a 1-yard run by Cal-Davis quarterback Jeff Bridewell and an 11-yard pass from West Virginia's Greg Jones to South Carolina running back Michael Dingle.

Walter Dean, the I-A All-America from Grambling, scored on a 3-yard run and Central, Ohio, wideout Eddie Britton caught an 11-yard touchdown pass from John Carroll quarterback Larry Wanke.

The game was played on a 78,000-square-foot sod field installed on top of the Florida Suncoast Dome's concrete floor. It was the first-ever football game played in the 10-month-old facility designed mainly for baseball.

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CHICAGO (AP) - Wales coach Mike Milbury had hoped to avoid a shootout in the NHL's 42nd all-star game.

But he, like everyone, should know by now that defense takes a vacation at the league's showcase event. And it was a typical offensive display Saturday when the Campbell Conference beat the Wales Conference 11-5.

''I don't think you want a 4-3 game,'' said Campbell coach John Muckler of the Edmonton Oilers. ''I feel sorry for the goaltenders because they're on their own. But there were some tremendous passing plays and great shots.''

Milbury, the fiery Boston coach known for vexing his frustration on the Bruins when they lose, joked about punishing his stars.

''There's a video meeting at 4:30 and then a skate with no pucks,'' Milbury said. ''All I asked was for a little backchecking.''

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HOUSTON (AP) - Canadian Carey Nelson is going home to look for a job, armed with a master's degree in economics.

He'll also return to Vancouver with a successfully launched marathon career after taking the lead in the 23rd mile to win Sunday's Houston-Tenneco Marathon in 2 hours, 12 minutes, 28.0 seconds.

''It's not going to become my life but I hope to come back and I'd like to make the Canadian Olympic team,'' Nelson said winning his second straight marathon. ''I've wanted to run the marathon in the Olympics since I was 14 years old.''

Varonique Marot of Britain won the women's event for the third time, overtaking Dutch runner Dorothe Rasmussen in the 17th mile and finishing in 2:30:55.

''It doesn't get any easier; it's still the same distance,'' she said of the title she first won in 1986 and again in 1989. ''I'm not enamored with the course. It's not that wonderful because of all the cement.

''But I love the people and I know the course, which helps against an experienced runner like Dorothe.''

Nelson, who ran and won his first marathon in Toronto last October, beat Czechoslovakia's Martin Vrabel.

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EAGLE RIVER, Wis. (AP) - Greg Goodwin of Zion, Ill., set a course record in winning the 28th Valvoline World Championship Snowmobile Derby.

Goodwin finished in 8 minutes, 27.863 seconds on the half-mile oval on Sunday, shaving 11 seconds off the mark set last year by Dave Wahl of Greenbush, Minn.

Dale Loritz of Green Bay was second in the 25-lap final event, often called the Indy 500 of snowmobile racing.

Gary Vessair of Canada was third; Chuck Decker of Eagle River, Wis., was fourth, followed by Goodwin's brother Jeff.

Wahl started on the pole position, led for 13 laps and appeared headed for another victory when his steering broke going into the third turn, causing his snowmobile to slam into hay bales.

''I wanted to kind of pace myself,'' Goodwin said. ''I was very glad Dave went out and set the pace, because I wanted to save something for the last few laps. Unfortunately he had the crash and went out of the race.''