Manager Bill Virdon, who transformed the Houston Astros from doormat into 1980's division champion, was fired yesterday by owner John McMullen with the team mired in fifth place.

First base coach Bob Lillis was named interim manager, and a team spokesman said "that will in all probability go through the end of the season."

"We made the decision that the Houston Astros were going to need a new manager next year and . . . in the interest of both the ballclub and Bill Virdon, this seemed to be the appropriate time to make the change," McMullen said.

Virdon, 51, has been the Astros' manager since late in the 1975 season, when they finished 42 1/2 games out of first. Under his guidance, they improved every year, challenging for the National League West title in 1979, winning it in a one-game playoff with Los Angeles in 1980 and losing it in a five-game playoff to the Dodgers last season.

In Richmond, a federal appeals court ruled the Baltimore Orioles do not have to pay attorneys' fees of $24,321 in a suit charging discrimination against disabled spectators in Memorial Stadium. The suit was brought by Disabled in Action, a citizens' group, and was settled when the city, mayor and ballclub agreed to provide facilities for the handicapped at the stadium.