The slightly swollen bruised right knee of quarterback Joe Theismann and the slightly confused bruised ego of rookie cornerback Tory Nixon were two of the discernible products of the Washington Redskins' 20-7 National Football League preseason victory over the Tampa Bay Buccaneers Friday night.

Assistant trainer Keoki Kamau said Theismann showed up at Redskin Park yesterday morning with a little swelling on his right knee, which was injured when he hit the ground on a third-down sack with 9:50 remaining in the first half at Tampa Stadium.

Theismann did not return to the game, although Coach Joe Gibbs said he planned to replace him with apparent No. 2 quarterback Jay Schroeder at that point anyway.

When asked if Theismann could play a game tomorrow (Sunday), if there were one, Kamau said: "Absolutely. If it was Dallas, he could play tonight (Saturday)."

Satisfied with that news, the coaches met for most of the afternoon yesterday to look at films of the game and evaluate the performances of those players who needed to play well to earn a job when the final 45-player roster is selected Monday.

One of them is Nixon, generally considered to be the eighth defensive back in the Redskins' plans. However, they are expected to keep only seven, barring injury.

Indications are the Redskins have held preliminary trade talks with several teams concerning Nixon, but have not come close to making a deal.

Apparently, the Redskins are trying to persuade teams to trade for Nixon based on his college performance, not his 1985 preseason play.

General Manager Bobby Beathard declined comment yesterday on the Redskins' plans for Nixon.

The team's top pick in the 1985 NFL draft, Nixon hardly was noticed when he played in the second half at Tampa, which is good, said assistant head coach-defense Richie Petitbon. But Nixon was used only sparingly on special teams, which might not be a good sign.

"I didn't have a chance to do anything," Nixon said of his play on defense. "I don't know. I'm in a tough situation. Even last week, I played well and had my guy covered all the time."

He admits that he has found the preseason frustrating at times.

"I don't know what they're looking for," Nixon said. "I'm trying my hardest and I think I'm doing fine. I'm not making any mistakes. I haven't gotten beat. I haven't gotten any passes caught on me since the Raiders game (when he twice was beaten deep on touchdowns that were called back because of penalties).

"I'm not going to give up. If something happens that I'm traded, if I'm cut, whatever, I'll think that they gave up too early on me.

"I'm going to play somewhere. I want to play here. I'm not pessimistic about it. I would hate to be. I never thought it (getting released) would happen, and I still don't. But if it does, it's reality. It's a possibility. I'll play somewhere. I'm not going to give up. "I know I can play."

Nixon is in the unenviable position of being the third-best rookie in the secondary. The Redskins are elated with the play of free safety Raphel Cherry and cornerback/strong safety Barry Wilburn, both later-round draft choices who are all but certain to make the 45-man roster.

Cherry and Wilburn have spent quite a bit more time learning the Washington defense than Nixon has. Nixon missed most of minicamp with a hamstring pull, then participated for only a short time in informal spring workouts before going home to help plan his wedding, then missed two weeks of training camp in a contract holdout. Cherry and Wilburn have not missed any work at all.

"Tory and I talked about (missing most of the informal workouts) and I told him what was at stake," Gibbs said. "He knew what he would be missing, but he had some things he felt like he had to do that were important to him. One was his marriage. Obviously, you're not going to miss your marriage."

Injuries may play a role in Monday's roster cutdown. Defensive end Steve Hamilton's pinched nerve in his right shoulder does not appear to be serious enough to place him on injured reserve, although he will undergo X-rays soon, said defensive line coach Torgy Torgeson. Gibbs said the status of Hamilton, wide receiver Gary Clark (sprained right knee) and defensive tackle Tom Beasley (injured right big toe) will be "analyzed" Monday . . . Running back Otis Wonsley experimented at H-back (man in motion) at Tampa to give the Redskins more "flexibility" with their four tight ends, Gibbs said. This doesn't mean the Redskins necessarily are thinking of releasing one tight end. Right now they have four: Clint Didier, Don Warren, Anthony Jones, and Rick Walker. If the Redskins keep three quarterbacks, they likely would have to cut one receiver (probably rookie Joe Phillips) and perhaps a tight end or a running back.