RIO DE JANEIRO — The McLaren auto racing team, the world champions of Formula One competition last year, maintained its domination in the first race for the 1985 title Sunday with a strong win by Alain Prost in the Brazilian Grand Prix.
Prost, 30, a French driver, took the lead early in the 61-lap race after Nelson Piquet of Brazil and Keke Rosberg of Finland, two former world champions, dropped out with mechanical problems.
Later, Niki Lauda, last year's world champion, also driving for McLaren, had to drop out, too, because of engine difficulties.
The only challenger at the end was Michele Alboreto of Italy, driving a Ferrari, who started from the No. 1 pole position in a field of 25.
Although Lauda was forced out of the race, McLaren proved that it is still the car to beat as Prost turned in the best lap time with an average speed of 115 m.p.h. per hour on the 31st lap.
A crowd of more than 85,000 watched the race for nearly two hours over the Jacarepagua circuit, where temperatures at noon on the asphalt track reached 110 degrees Fahrenheit.
Brazilian fans, hoping for a comeback by former world champion Piquet, driving for the Brabham team, were given an early surprise when Piquet spun off the track in the third lap, hit the guard rail and dropped out. Traffic was heavy as the contenders jockeyed for the lead, and Piquet narrowly avoided a crash with Nigel Mansell of the Williams team.
As Prost earned his 17th win in Grand Prix competition, he began a new attempt to win the individual title that has narrowly escaped him for the past two years. Last year, Prost lost to his McLaren teammate, Lauda, and two years ago he lost to Piquet.
Since Piquet was gone after the third lap, the new Brabham car could not be tested. The other Brabham entry, driven by Francois Hesnault, also droped out after a collision with an Alfa Romeo driven by Eddie Cheever, one of the few U.S. drivers in Grand Prix competition now.
However, the Lotus team of Airton Senna of Brazil and Elio de Angelist of Italy made a good showing, living up to early expectations that the Lotus may be a serious challenger this year.
De Angelist finished third, and Senna, the hometown favorite, was in contention for most of the race until an electrical failure put him in the pits at the 44th lap. He was unable to return, but the Lotus team of young drivers is a threat.
Alboreto's second-place finish with the No. 1 Ferrari car showed that the red Italian Ferraris are also going to be a challenger.
The next race in the series will be at Estoril, Portugal, April 21.