Washington Redskin General Manager Bobby Beathard, who has been working for weeks to obtain additional selections in the National Football League draft April 28, swapped No. 1 picks yesterday with the Los Angeles Rams in order to obtain two other high-round picks, one of them in the second round.

Both teams agreed not to announce details of the trade beyond the fact that they had exchanged first-round picks. But Beathard previously had said he would not trade his No. 1 unless he obtained at least a No. 2 in return. Another choice, most likely a No. 4, also was involved, although Beathard refused to confirm what he received from Los Angeles, other than to say they were "high choices."

To pull off the deal, the Redskins had to surrender the ninth position in the opening round. Now they will select 20th, which Beathard admitted all but ends their hope of obtaining a defensive lineman in that round.

"It's doubtful that we will be able to get a defensive lineman now," he said. "I hate to say it, but we will have to take the best athlete available when it's our turn. That could be an offensive lineman, a running back or a wide receiver, maybe even a quarterback.

"We're really excited about this deal. It gives us a lot of options now. We needed more picks because this is a quality draft loaded with a lot of good players. Now we can add some depth, even if it means bypassing the ninth-best player in the draft. But we've gone all over the possibilities and we are sure we can get a real good player on the 20th pick. If we weren't sure, the trade wouldn't be a good one."

Before the trade, the Redskins were missing second-, third-, fourth-, seventh- and 10th-round selections. Now, out of the key first five picks, they apparently lack only a third. And, Beathard said, he will continue trying to trade for even more choices.

Among the quality players likely to be available in the first round when the Redskins make their selection are tight end Clay Brown of Brigham Young, receiver Cris Collinsworth of Florida, defensive end Donnell Thompson of North Carolina, tight end Benjie Pryor of Pittsburgh, running back Jarvis Redwine of Nebraska, offensive tackle Curt Marsh of Washington, fullback Booker Moore of Penn State and tight end Dave Young of Purdue.

Last year, the Redskins selected 16th in the first round and took receiver Art Monk, who became one of the four or five best rookies in the league. Beathard said yesterday he saw no reason "why we can't come up with someone just as good as Art."