Mike Thomas signed a new contract today but the Washington Redskins had a new worry because Pat Fischer's football career apparently is in jeopardy.

On another one of those frantic days in training camp, Thomas signed a one-year pact "I can live with," ending six months of long and often bitter negotiations between the third-year running back and the club. Thomas is believed to have signed for $110,000 for the 1977 season.

But while that was being accomplished and George Allen was lopping 19 players off his active roster, including Thomas' older brother Earl, Fischer was back in Washington checking into Sibley Hospital for more treatment of his painful back.

Fischer's problem has been diagnosed as a pinched nerve. The little cornerback has been saying publicly, "There's not the slightest bit of doubt in my mind that I'll play this year," but team sources are far more pessimistc about Fischer's chances for recovery.

Allen was not among the skeptics, however. "Pat's a tough guy and if anyone can play, it'll be him," he said. "I haven't written Fischer off, not by any means."

Team physician Stanford Lavine declined to talk about the chances for Fischer's recovery, saying only that he would be placed in traction, told to rest and given therapy to ease the pain the strengthen the damaged area. The present plan, he said, is to avoid surgery.

The next two weeks will be critical for Fischer. If he does not show significant improvement, an operation would be necessary and that would eliminate Fischer this season. It probably also would mean the end of his brilliant 17-year career.

"I'm going to play this year unless they've got somebody "better than me," Fischer said from his hospital bed. "Right now, I'd say it's probably the same as it was last week. I feel a little better, and at least we know what it is now. It's not the same problem [a disc injury] I had in 1971. If that were the case, there would be a lot more cause for concern. Now we just have to wait and see what happens."

The burden of replacing Fischer - for now - will fall upon the shoulders of third-year-man Gerard Williams, whose preseason debut against the Browns Monday night was spotty, at best. Allen insisted, "For his first game, he did an acceptable job."

But Allen has had a history of striking quickly in the trade market for a seasoned veteran after a crisis, and if Fischer cannot play this season, that will probably happen again.

"It's still too early to even think about that," Allen said. "Gerard will play the whole game against Miami. He has a lot of ability. And I think Pat will make it back."

Already the rumor mills are beginning to turn with some familiar names mentioned as possible trade targets. How about Mei Blount, the disgruntled Steeler holdout. "Not a chance," said Pittsburgh president Dan Rooney. "The Redskins haven't called about him, and as far as we're concerned, we wouldn't consider it. We want him playing here this season."

Lem Barney of Detroit and Lamar Parrish of Cincinnati also are said to be available at the right price. "But you hear that kind of talk every year," said Bobby Mitchell, the Redskin director of pro scouting. "It would be nice, but not very realistic."

What about Bryant Salter, the versatile defensive back the Redskins traded to Miami last summer for Jake Scott? Salter, 27, played out his option and was dropped by both Miami and Baltimore in 1976. He now is "retired" and working at the State Department in Washington but would jump at the chance to play again for the right price, according to his friends.

Salter last year was seeking a contract in the $100,000 range. At this point, the Redskins don't seem to be that desperate, particularly since Salter's best position is free safety. Nevertheless, he filled in for Fischer at cornerback in 1975 and he knows the system.

The Redskins spoke with Salter several times during the offseason about rejoining the team, and in an emergency, they just might call again.

Thomas had his big day spoiled when he learned that his brother Earl, a veteran wide receiver, had been cut from the roster.

"I should be happy about the contract, and I am," he said. "And now I've got to take my brother to the airport. It's been a weird day, know what I mean?

"I'm getting a great raise from what I made in the past (about $30,000 last season). I did want a long-term contract, but we could never come to an agreement on that. In a sense, this is not the greatest contract for Mike Thomas, but it is an improvement."

Thomas has spent the last two weeks worrying about the contract and limping around with a hamstring strain in his left leg.

He said he would increase his activity this week in practice, but that he would not rush his conditioning. "I'm not looking to make it any worse," he said. "If I can't run right I can't cut, and if I can't cut, I can't play this game. I'm just going to try and ease back into it."

Nineteen players were eased off the Redskin roster today. In addition to the cut of Thomas, eliminated mostly because he didn't play on the special teams, the only other semi-surprise was the waiving of rookie running back Mike Northington.

Northington, the team's ninth-round draft choice from Purdue, left camp after four days the first week, then returned eight days later after the Redskins convinced him they still believed he was a prospect.

In a mild upset, the Redskins released wide receiver James (silk) Thompson, who spent the 1976 season on the team's injured reserve list. Thompson, who played in the World Football League, also was a victim of the numbers game at the Redskins most overstocked position.

By 8 p.m., the Redskins head released the names of 11 players who had been placed on waivers, and said that defensive tackle Tyrone Dye will stay on injured reserve because he has a broken foot.

Also cut today were punter Merritt Kersey, West Chester; place kicker Bob Berg, New Mexico, guards Terry Shelsta, Dakota Wesleyan and Joe Davis, USC; linebackers Mike Mitchell, William Penn and Tom Poe, Washington State, and running back James Richards, Florida.

They said they still had not notified the remaining seven players of their final disposition, and would release the names when that was accomplished.

Allen said a review of the game films of the Redskins' 16-14 victory over Cleveland indicated "too many darn mistakes," though he said a pass interference judgement against Gerard Williams on the Browns second touchdown drive was "a bad call." . . . Terry Hermeling is expected to move back to right guard and Tim Stokes should begin starting at left tackle when the Redskins resume practice Wednesday afternoon.