After an evening of soaring emotions Friday, the Washington Redskins were brought back to earth with a jolt yesterday when they placed center Jeff Bostic on injured reserve until at least Oct. 15, which is five days before the seventh game of the season.

Bostic, who suffered extensive ligament damage to his right knee last October in a game at St. Louis and underwent reconstructive surgery during the offseason, has been practicing for several weeks. He had said as late as Friday that he might be able to play in the season opener at Dallas Sept. 9.

But the Redskins made a trade yesterday, obtaining second-year offensive tackle Dan McQuaid from the Los Angeles Rams for an undisclosed 1986 draft choice.

To make room for McQuaid, who is 6 feet 7 and weighs 278 pounds, the Redskins placed Bostic, their starting center the past four seasons, on injured reserve.

Meanwhile, in the wake of the Redskins' 37-36 come-from-behind victory over New England at RFK Stadium Friday night, it appears that veteran kicker Mark Moseley controls his destiny in his competition with Tony Zendejas.

"It's like a heavyweight fight," special teams coach Wayne Sevier said yesterday. "You've got to win by a knockout. Obviously, Tony hasn't knocked him out yet."

Moseley has made three of five field goals in preseason, including kicks of 38 and 47 yards Friday. Zendejas is one for four, including a 42-yarder against New England.

"I said before that if both continued to do poorly, it was to Mark's advantage," Sevier said. "Now, both have done well in a game, and I don't think our opinion has changed. Mark has a little advantage."

It may be more than a little. Although Zendejas arrived with great credentials in the U.S. Football League, even some of his supporters in the organization now wonder if he will make the team.

And, for the first time, there is a hint that the coaches are considering making a move with the kickers by Tuesday's cutdown of 10 players to a 50-man roster. Previously, it seemed certain that this competition would go to the final 45-man roster cut Sept. 2.

"I doubt anything will happen this Tuesday, but it's possible," Sevier said. A trade seems unlikely until the season starts and some teams become unhappy with their kickers.

Zendejas said his hopes rest on having another good game at Tampa Bay Friday. But it may already be too late for him.

"When Mark wasn't doing well, Tony didn't pick up on it," Sevier said. "That was a chance for him."

Other issues surfaced yesterday. Just how much did quarterback Babe Laufenberg help himself by bringing the Redskins back to win the game with four seconds remaining?

General Manager Bobby Beathard said Laufenberg did "a terrific job." All indications are that the coaches did not discuss the ranking of backups Laufenberg and Jay Schroeder in their meetings yesterday, but did bring up the option of keeping just two quarterbacks.

Coach Joe Gibbs, who is said to favor keeping three quarterbacks on the 45-man roster, brought up for the first time Friday the possibility of keeping only two.

"It's going to hurt not having a player who can play 25-30 plays a game," he said. "You'd be making a tough decision to keep a spot open for a player like that (a third quarterback), but it may be one that we feel is best for us."

In the injury department, wide receiver/punt returner Gary Clark, almost certain to make the team, suffered a sprained knee in the game, head trainer Bubba Tyer told the coaches yesterday.

Clark, who apparently was hurt before he made his 75-yard touchdown catch late in the game, reported to Redskin Park for treatments when his knee swelled yesterday morning. He is expected to miss from one to three weeks.

Clark is a major part of one kick-returning scenario. He and Michael Morton, a kickoff returner, may make the team in place of veteran Mike Nelms, who handles both punts and kickoffs.

"That's one way to pencil it in," said Sevier. "But Clark's injury complicates the situation."

In Bostic's case, the National Football League allows a team to bring back one player to the active roster from its preseason injured reserve list, but that move cannot be made until after the league trading deadline, which is Oct. 15.

Any other players brought back from the preseason list must clear waivers.

It's likely the Redskins will use that one move to bring back Bostic.

"We don't know," Beathard said. "We'll just have to wait until that time and see what our situation is then."

The offensive line's worst fears now have been realized. Joe Bugel, the assistant head coach-offense who is in charge of the line, has been very concerned about depth there. "It's frightening," he said at the team's training camp.

Rick Donnalley, Bostic's replacement last season, will start at center, with Russ Grimm and Ken Huff at guard and Mark May and Joe Jacoby at tackle. George Starke, at 37 the oldest tackle in the league, is the only experienced backup and appears to have a spot on the roster. After that, it's anyone's guess who will fill in the other two spots, if the Redskins keep eight offensive linemen.

Tackle Mike McClearn has been playing well recently after returning from a finger injury, and rookie guard Raleigh McKenzie appears to have won a job. The presence of McQuaid gives the Redskins more options.

"He looks very good in films," Beathard said of McQuaid, who played at Nevada-Las Vegas and spent last season on injured reserve with the Rams.

"He has played extremely well in preseason. We think he will be a heckuva guy to work with."

The Redskins' offense seems to do doing quite well despite the insecurities of the line.

"I really think we're becoming the complete football team," said Joe Theismann, who threw for 249 yards in the first half compared to Laufenberg's 200 in the second.

With wide receiver Charlie Brown watching with a sore left hamstring, Calvin Muhammad played with his dislocated left middle finger taped tight and caught four passes for 83 yards.

Brown, who probably would have played had this been a regular season game, has missed most preseason practices, so it's logical to wonder if Muhammad hasn't joined Art Monk as a starter.

"With three guys of that caliber, it's ideal," said Beathard. "In meetings, Joe (Gibbs) never differentiates between them. I wouldn't even think we know who's the backup."

Muhammad missed the first two preseason games with his injury but apparently has little to do to improve on his timing with Theismann. So expect more of the same long passes in the coming weeks.

"We're really working hard on trying to get the ball up the field in that particular style," Theismann said.

It's uncertain who will back up Theismann this weekend. Laufenberg drew raves yesterday, but most were quick to point out that Schroeder led the team to its winning score at Los Angeles the week before.

Nonetheless, Laufenberg felt vindicated. "If that's not good enough, that's not good enough. I played as hard as I can play," he said.

When asked if he was the team's best-kept secret, he said, "I'm like Watergate. I'm leaking out, I think. Slowly but surely."

Veteran strong safety Tony Peters did not play because of a mild hamstring strain. He is expected to practice this week. Rookie defensive tackle Dean Hamel injured his back slightly in the game, but did not receive treatment and is expected to practice as well.