Prost, 38, Announces Retirement : Auto racing: Closing in on his fourth Formula One championship, the driver decides to go out on top at end of the season.

Every great athlete wants to go out on top, but few do.

Many race drivers, notably A.J. Foyt, Richard Petty and Johnny Rutherford in recent years, appeared to have stayed too long in the cockpit.

Alain Prost, about to become Formula One Grand Prix racing’s four-time champion, is apparently doing it differently, leaving at the peak of his remarkable racing career. The little Frenchman, known as “the Professor” because of his precise manner in the art of high-speed driving, announced Friday in Estoril, Portugal, that he will retire at the end of the season.

“I want to leave at the summit,” Prost, 38, told writers on hand for Sunday’s Portuguese Grand Prix. He has won seven of 13 races this season, and another victory Sunday would give him his fourth championship with two races left, Japan and Australia.

Only Juan Manuel Fangio of Argentina, with five, won more Formula One championships. Prost’s 51 Grand Prix victories with Renault, McLaren, Ferrari and Williams far outdistance runner-up Ayrton Senna of Brazil with 39.

Ron Dennis, managing director of the rival McLaren-Ford team, has called Prost “probably the best racing driver in the history of motorsports.”

Prost drives a Williams-Renault for Frank Williams. His retirement probably will set off massive movement among Grand Prix drivers.

Senna, Prost’s bitter rival and former teammate, announced earlier that he will leave McLaren next year and is rumored to be Prost’s replacement with Williams. Then Michael Andretti left McLaren abruptly with three races remaining, leaving Mika Hakkinen of Finland as the team’s lone driver.

Prost’s teammate, Damon Hill, has won the last three races and is the only driver with a mathematical chance of catching Prost. He is the son of the late Graham Hill, a former world champion. Prost has 81 points to 58 for Hill and has won three times at Estoril.

Prost won consecutive championships in 1985 and ‘86, driving for McLaren. It could easily have been four in a row. In 1983, he led Nelson Piquet of Brazil by two points going into the final race but lost by two when mechanical problems beset his Renault.

“I’ll never come that close without winning again,” Prost declared.

But a year later, after moving to McLaren, his losing margin to teammate Niki Lauda of Austria was only half a point.

He won his other title in 1989 when he and Senna were teammates and finished 1-2. In 1990, Prost switched to Ferrari and finished second to Senna’s McLaren.

Prost won the French and European kart championships when he was 20 and the European Formula 3000 series when he was 23, earning him a Formula One seat with McLaren in 1980. He jumped to the French Renault team in 1981 and won his first Grand Prix in his native France.

This will be the second retirement for the controversial Prost, who sat out the 1992 season after having been dropped by the Ferrari team. However, early in 1992, he was signed by Williams to drive in 1993, setting up a prickly situation that led to Nigel Mansell’s leaving the team despite having won his first championship.

“Obviously, what I did (14 poles and nine victories) and what my teammate Riccardo Patrese did (six seconds and one victory) wasn’t enough,” an embittered Mansell said before deciding to race Indy cars for Carl Haas and Paul Newman, for whom he won the PPG Cup title last week.

Last June, Mansell traveled to England to accept the Ford Seagrave Trophy for outstanding achievement in motor sports and couldn’t resist taking a jab at Prost.

“I’ll tell you this,” he said. “If I was still there racing in the Williams, I don’t think Prost would have won any races at all.”

Although Prost said he had been considering retirement since early in the season and decided to make it official Friday, there has been speculation that he might follow Mansell across the Atlantic into Indy cars. He is nearly two years younger than Mansell, who turned 40 last month.

In his announcement, however, he gave no such indication.

“It is a decision that I have reached after careful consideration throughout the year,” he said. “It has not been taken in a hurry at all. I reached the final decision about a month ago but could not make the announcement at Monza because of the circumstances of the race.

“I feel after so many years at the top that I should be allowed to take a rest. It has been a long and difficult career. I feel I have given a lot to the sport, and I want to leave with a smile on my face.”