Ricky Rudd was hot, tired and leading second-place Joe Ruttman by more than a lap when he looked at the Martinsville (Va.) Speedway scoreboard and saw there were still 100 laps to run.

"Anything can happen in a short track race," Rudd, 29, of Chesapeake, Va., said as he enjoyed a bit of shade and a cold drink after winning yesterday's Sovran Bank 500 NASCAR stock car race. "Things can happen so quick out there that I just wasn't going to let up. I really ran the car the last 150 laps like we the top two cars were in the same lap."

The air temperature yesterday was in the mid-80s and the track temperature exceeded 110 during the grueling 500-lap race. The heat was a factor in the attrition rate among the leaders.

Dale Earnhardt, who was trying to become the first NASCAR driver to win three straight races since Bobby Allison did it late in the 1983 season, complained of feeling ill because of fumes shortly before his engine blew on lap 147. Of the seven leaders, four others failed to finish and another was far off the pace. Nineteen cars were running at the end.

Rudd, driving a Ford Thunderbird for longtime car owner Bud Moore, averaged 76.882 mph and crossed the finish line more than a lap ahead of Ruttman's Buick LeSabre. It was Rudd's fifth career victory and the first triumph on this track for a Ford since Richard Petty did it twice in 1969.

Terry Labonte was third, rookie Alan Kulwicki fourth . . .

Defending world champion Alain Prost, exploiting the few drops of gasoline left in his McLaren-TAG car, outdistanced Nelson Piquet and won the Grand Prix of San Marino in Imola, Italy.

To earn his 22nd career Grand Prix victory, Prost, 31, zigzagged through the last two bends of the race to have the engine pick up its remaining fuel . . .

Bob Tupper of Woodbridge won the 50-mile Formula Vee feature race at Summit Point Raceway by 5.6 seconds over Ed Womer of Harrisburg, Pa., as the track opened its season.

Tupper drove a Zink SWT, averaging 80 mph over the two-mile, 10-turn circuit.

Tom Wareham of Lorton, Va., drove a Corvette to a 3.8-second victory over Bruce Neild of Arlington (Corvette) to win the showroom stock Mid Atlantic Road Racing series event. TENNIS

Third-seeded Joakim Nystrom of Sweden beat Yannick Noah of France, 6-3, 6-2, to win the rain-reduced final of the $325,000 Monte Carlo Open in Monte Carlo, Monaco. Nystrom, 23, picked up $58,500 for his fourth tournament victory of the year.

The final, reduced from five to three sets because a shower held up the start for 90 minutes, was played in light rain.

Both players committed unforced errors and Noah's serve was ineffective. "I was not into the game. I wasn't thinking about the match because this morning I had a little daughter and that for me is more important," said Noah, whose wife Cecilia gave birth to a baby girl . . .

Jimmy Connors won his second straight Bank of Oklahoma Classic, beating Kevin Curren, 6-3, 6-2, in the rain-shortened, windy event in Tulsa . . .

Top-seeded Elise Burgin earned her first pro championship with a 6-1, 6-3 victory over Tine Scheur-Larsen in a Virginia Slims tournament in Isle of Palms, S.C.

Burgin, 24, of Baltimore, earned $12,000 for the victory on the clay courts at Wild Dunes Resort. "People always say that it takes a while to sink in," Burgin said of her first pro victory. "But I want to tell you, I'm ecstatic." HOCKEY

Czechoslovakia routed the United States, 10-2, and West Germany and Poland tied at 5-5 on the final day of the consolation round at the World Hockey Championships in Moscow.

As a result of the tie, Poland dropped out of the top eight-team group for next year's World Championships in Vienna.

Czechoslovakia (5-4-1) finished fifth. The U.S. team (4-6) ended sixth. OLYMPICS

International Olympic Committee President Juan Antonio Samaranch says that if North and South Korea cannot settle by June their dispute over where Olympic events should be held, North Korea probably will boycott the 1988 Summer Games in Seoul. "We are arriving at a level where we have to reach agreement, or no agreement," Samaranch said. "I think if there is no resolution in June, that to get a resolution after this date will be too late."

He said he did not know if other communist-bloc countries would join with North Korea in a boycott. RUNNING

Jon Sinclair of Fort Collins, Colo., outkicked Dirk Lakeman of Eugene, Ore., in the stretch to win the eight-kilometer The Athletics Congress men's national championship race in Portland, Ore.

Sinclair, 28, was clocked at 22 minutes 44 seconds and earned $3,000. Steve Spence of Fairfax, Va., finished third. COLLEGES

An Alabama football player was killed and another critically injured Saturday night in a high-speed auto crash in Huntsville, Ala., authorities said. A former player and one other person also were injured.

Police said George Scruggs, 20, of Decatur, Ala., died at Huntsville Hospital after the crash. Scruggs was a freshman who had made second string as a running back after being redshirted.

Injured was Verner Wilkerson, 22, of Enterprise, Ala., listed in critical condition with head injuries in the hospital's intensive care unit. Former player Marvin Humphries, 22, of Montgomery, was released from the hospital yesterday. TRACK

Carl Lewis, coming back from a hamstring injury that slowed him last season, won the 100-meter dash and extended his long jump victory string to 46 meets at the Puma-Mount SAC Relays in Walnut, Calif.

Lewis, winner of four gold medals at the 1984 Olympics, seemed in less than top form in both events, winning with what were, for him, mediocre marks.

He won the 100 in 10.14 seconds and took the long jump with a wind-aided leap of 27 feet 4 inches.

Evelyn Ashford, another 1984 Olympic champion who was sidelined last year, also continued a comeback. She won the women's 100 with a time of 11.11.

Jud Logan broke the U.S. record for hammer throw with his best effort of 265 feet 4 inches. LOCALLY

The Washington Redskins Chapter of the NFL Alumni will be host of its seventh NFL Alumni Charity Golf Classic May 5 at Indian Spring Country Club. The tournament will pay tribute to longtime chapter member and tournament director Andy Stynchula, who died in a car accident last August. Alumni golfers will include Sam Huff, Bobby Mitchell, Willie Wood and Jim Ricca. Redskins expected are Coach Joe Gibbs, Jeff Bostic, Russ Grimm and Joe Jacoby.