Michael Andretti charged to the lead at the start and then held off a challenge from his father, Mario, to win the Budweiser-G.I. Joe's 200 yesterday in Portland, Ore., his second Indy-car victory in as many weeks.

The younger Andretti led all but three laps, falling briefly behind his father only because of pit stops.

Michael finished 3.92 seconds ahead of his father. His average speed of 110.673 mph was a track record, breaking the mark of 103.984 set by Emerson Fittipaldi last year.

Al Unser Jr. finished third, holding off a strong late challenge from Danny Sullivan. Sullivan started from the pole but was passed by Mario Andretti on the 26th lap and lost further ground during his second pit stop.

The father-son team from Nazareth, Pa., dominated in their Newman-Haas Chevrolet-powered Lolas. Michael Andretti was in firm control on the sun-drenched, nine-turn Portland International Raceway course in a performance nearly identical to last week's, when he won at Detroit by almost a lap.

Andretti, 27, has won 11 times in eight seasons of Indy-car racing.

In 1986 the Andrettis finished 1-2 at Portland. But in that Father's Day race, Michael ran out of fuel on the last lap and lost to his father by .07 seconds, the closest finish in modern Indy-car history.

"We finally broke the ice in Portland," Michael said. "It was just a great day."

Miller 400: Dale Earnhardt took advantage of Bill Elliott's blown engine to end his own slump with a victory at Michigan International Speedway in Brooklyn.

Elliott led 102 of the 200 laps on the two-mile, high-banked oval before his engine blew on Lap 186.

That left the battle to three-time Winston Cup champion Earnhardt and winless Ernie Irvan. Earnhardt's Chevrolet Lumina inherited the lead when Elliott's engine blew, but Irvan's Oldsmobile Cutlass took the top spot on Lap 188 before Earnhardt asserted himself, moving in front on Lap 195 and winning by 0.14 seconds.

Mexican Grand Prix: Alain Prost of France flashed past Ayrton Senna, his chief antagonist and former teammate, with 10 laps to go and went on to pace a 1-2 Ferrari finish in Mexico City.

Prost won his 41st career race and second this season by 25.351 seconds over Briton Nigel Mansell, who was .179 seconds ahead of Austrian Gerhard Berger.