Earl Campbell, running back for the Houston Oilers, was sent in a surprise, seemingly hastily arranged trade today to the New Orleans Saints in exchange for their top choice in the 1985 NFL draft.

Campbell, 29, a powerful 5 feet 11, 238 pounds, has been a mainstay of the Oilers' offense since 1978, when he was a No. 1 draft choice out of the University of Texas. The trade reunites him with Coach Bum Phillips, his coach at Houston before coming here in 1981.

Phillips said Campbell will play Sunday against the Los Angeles Rams in the Superdome.

The acquisition of Campbell from the Oilers, winners of just three of their last 31 games and 0-6 in 1984, was surprising because running back is one of the few positions on the Saints' roster well stocked with experienced, healthy people.

The Saints, 3-3 and aiming for their first playoff appearance, are hurting on the offensive line after injuries to three starters.

But they have productive ball-carriers in George Rogers, Wayne Wilson, the rapidly developing Hokie Gajan and draft choice Tyrone Anthony.

The trade gives the Saints two Heisman Trophy winners in the backfield -- Campbell and Rogers.

Campbell entered the 1984 season as the ninth-leading rusher in NFL history; he had carried 1,883 times for 8,296 yards, a 4.4 average. But he had harder times this season with the Oilers, carrying 96 times for 278 yards, a 2.9 average.

Phillips said the Oilers made the offer after noon today, NFL trade deadline day, when Ladd Herzeg, Houston general manager, called Saints executive Pat Peppler.

"Obviously, we are glad to get him," Phillips said. "I've never had too many good players. This trade gives us a heck of a backfield.

"I doubt if he and George (Rogers) would play in the same backfield in too many situations, but they might. Earl is a tailback in the I-formation. That's what he does best. I never talked to the Oilers about this trade before."

"The Saints called regarding Earl's availability," said Herzeg. "But it was an extremely difficult decision because he has meant so much to this franchise."

Campbell gained 1,450 yards as a rookie in 1978, then 1,597 and 1,934 the next two seasons -- easily the best three-year start ever in the NFL. He tailed off with Phillips gone, yet in his last two full seasons gained 1,376 yards in 1981 and 1,301 in 1983.

The trade raised the possibility of an early move by the Oilers to come to terms with and activate former Nebraska star Mike Rozier, another Heisman runner who began his pro career this year with the Pittsburgh Maulers in the USFL.

"I think bringing in Mike Rozier at this time would put undue pressure on the young man," said Herzeg, who last month negotiated a buyout of Rozier's USFL contract. "I think it would be best for us and Mike if we brought him in fresh for 1985."

"I think this is a business I'm involved in," Campbell said in parting. " . . . In the sports business, you have to get traded around sometimes. I hope it's good for them (the Saints) and I hope it's good for me."

Hugh Campbell, the Oilers' first-year coach, said Earl Campbell's attitude was not a problem during the dismal start to the season.

"Earl was most cooperative in the year that I've worked with him and it hurts to see him go," the coach said. "But I'm glad to see him go where he will have a coach that will take care of him."