O. A. (Bum) Phillips, who defied team owner Bud Adams' midseason order to hire an offensive coordinator, was fired yesterday by Adams as coach and general manager of the Houston Oilers.

There was immediate speculation that Phillips would be hired to coach the lowly New Orleans Saints. Steve Rosenbloom, general manager of the Saints, said Phillips would be considered a candidate for the job.

Phillips, one of the National Football League's most colorful coaches, took the Oilers to the playoffs the past three seasons as a wild-card team. The Oilers lost to the Pittsburgh Steelers in the 1978 and 1979 AFC championship games, bringing a Phillips vow last year that the Oilers, who he said were knocking on the door of the Super Bowl, "would kick down the s.o.b." in 1980.

However, Oakland routed the Oilers, 27-7, in the AFC wild-card game Sunday. Oakland cornerback Lester Hayes described Phillips' two-tight-end attack designed for running back Earl Campbell as "something that looked like it came out of the 1940s . . . It was the type you see with simple blocking patterns from high-school teams."

In the three playoff losses, Campbell gained a total of only 168 yards. The Oiler offense, which scored 365 points in 1979, produced 20 percent fewer -- 291 points -- this season, and Adams said he asked Phillips at midseason to hire an offensive coordinator or elevate one of the three current offensive assistants to the position. Phillips declined, saying the team didn't need one.

Adams said yesterday, "Bum's adamant refusal to even consider the possibility the offense needed some fresh blood and input weighed heavily in my decision . . . Bum has done a fine job over the past six seasons in bringing our team to its current level of development.

"At the end of each season, I always sit down and evaluate the job that has been done and determine if we made the degree of progress we were looking for prior to the beginning of training camp. In recent years, I have felt we have taken significant steps forward but after this season I feel we have taken a large step backwards."

In six seasons, Phillips' record was 58-35. In the six seasons prior to his arrival, the Oilers were 22-58-2. None of the Houston coaches prior to Phillips had lasted long. Adams fired Ed Hughes after one season (1971), Bill Peterson after one year and five games and Sid Gillman after a year and nine games.

Even Phillips' players criticized him publicly lately and linebacker Gregg Bingham said yesterday, "I think some good things can come from this. There were a lot of things that went on during the season that I don't want to talk about . . . If they get the right coach, this could be good."

Phillips said he was shocked after being called into Adams' office yesterday morning and being told he was fired. He said, "The last time I talked to Bud Adams about this was concerning extending my contract; then they fire me."

Phillips told the Associated Press, ". . . I'm not bitter. Hell, he owns the club and he can do anything he wants to with it."

Phillips, who had one year remaining on his contract, said he intended to coach in the NFL next season, but he would not say where. However, sources around the league say that they expect him to become the next coach of the Saints. Those sources also said he had not been among those coaches contacted about their availability if the Washington Redskins fire Jack Pardee as coach.

In Uppervile, Va., Redskin owner Jack Kent Cooke, said, "I have no comment; in fact, I have less than no comment" concerning Philips' availability. Cooke's position has been that he currently has a coach and that he will not talk about a Pardee replacement unless, or until, he decides to fire him.

Phillips, known for his cowboy hat, snakeskin boots, chewing tobacco and crew cut, started his career as the head coach at Texas-El Paso in 1962. His first pro coaching job was as defensive coordinator for the San Diego Chargers from 1967 until 1971. He went back to the college ranks as an assistant in 1972 and 1973 before being named Houston's defensive coordinator in 1974. The next season, he became coach of a mediocre team and two seasons later also assumed the gneeral manager's duties.

Ladd K. Herzeg, Oiler senior vice president and chief administrative officer, will take over as general manager. Herzeg said he expected to name a new coach soon and that he wanted to retain as many current Houston assistants as possible.

Many Houston fans, who had cheered Phillips' winning teams and his cowboy ways, were shocked and angry at his firing. Several fans picketed the Oilers' practice field, some carrying obscene signs.

"There's just no gratitude in this world, no matter who you are. Bud has struck again," bookkeeper Lorene Wiatt said.

"You can't please Bud Adams," construction foreman Phil Green said. "You will not replace Bum Phillips. You will get another coach, but you will not get another Bum Phillips."