Bobby Beathard put his weathered neck on the line once more yesterday -- and again begged comparisons with the Redskins general manager he replaced. George Allen was near jogger's death after five laps around the track at Redskins Park; Beathard could do 150, if he cared to.

In seven years here, Allen swam against the NFL mainstream. But he did it predictably, swapping draft choices for veteran players. Beathard is a trading tornado. Only he could make three plus five plus five plus two equal one. And a center nobody else thought worth a snap seem like a future all-pro.

The Redskins bottom line is this: in about four hours yesterday, from midmorning to nearly noon -- and while doing nothing more strenuous than loitering around the office in running shorts and a torn T-shirt -- Joe Theismann became a dramatically better quarterback. That is because the Redskins acquired for their offense two rocks and a rocket.

"From famine to feast," Theismann said, realizing that with Joe Washington the Redskins got a player who might put him in the NFL record book and that with Mark May and Russ Grimm they got players who might keep Harvey Martin and Randy White from swallowing him whole.

They still don't have any linemen who could stop Nancy Reagan on third and short, but three men who can help keep the defense watching the action more often than participating in it helps. Both offensive tackle May and halfback Washington are, in football lingo, "guys who can sing solo."

That means they are at least one cut above the ordinary, men who can be trusted with special roles, who make the chorus worth paying dearly to watch. May may be more valuable; Washington will be more exciting. To defenders, he is like tackling a ghost.

A stubborn ghost.

And a proud one.

We learn as much by examining Washington's career as by talking with him. Without being stuffy, he seems to demand attention, because he believes he deserves it. He is excited about being traded by the Colts yesterday because he knows he will be the prime back with the Redskins.

With Washington's diminutive stature, there always is the question of durability, the possibility of some behemoth waddling off the field scraping Little Joe off his cleats. That is why his value has declined in five years, from the fourth player selected in the '76 draft to costing the Redskins a second-round pick yesterday.

At Oklahoma, Little Joe was what coach Barry Switzer would call a stud horse in as fine a stable of runners as any school might lasso in any comparable period.

"You name the good ones, we had 'em," Washington said.

Greg Pruitt. Mike Thomas (briefly). Joe Wylie. Leon Crosswhite. Elvis Peacock. Billy Sims. Kenny King. Horace Ivory.

In his fashion, as a combination runner-receiver-catcher, Washington was a good as any of them. When he realized last season the Colts considered rookie Curtis Dickey his superior, he demanded either to be traded or given enough of a money pad to make sitting on the bench comfortable.

Anyone who considered the Washington maneuver somewhat of a gamble was astonished at what trickled from Beathard's sleeve as the day wore on. And after peddling the Redskins' first-round choice next year to the Rams for a third-round pick and two-fifth-round picks this year and a second-round pick in '82, he actually made it sound logical.

The Redskins' major need in '82 still will be defensive linemen, he said, and only two juniors project as excellent. By their turn in the '82 draft, Beathard believes, both will have been chosen by other teams.

"We don't plan to be 6-10 next year," he said.

Grimm is one of the reasons. Beathard is betting his travel card and stopwatch that he has slickered the rest of the league, that third-rounder Grimm will be the center of the Redskins' offense for years.

That the NFL draft is the same week as the Kentucky Derby is highly appropriate, for judging human flesh is the most important gift in football. There are only so many Xs and Os, after all, just two basic offensive options -- run or pass. The great teams are the ones that can sift the prospects from the suspects, who know that their third-round draftee is better than someone else's first-rounder.

Beathard said Grimm is the top available center, the 20th best senior in the nation, a budding Len Hauss of Mick Tingelhoff, two other obscure collegians who became all-pros at the position. Although Paul Brown once made one the first player chosen for his Cincinnati Bengals, centers usually are ignored until the later rounds. Exceptional ones rarely wear out before 12 years.

How good is Beathard? How clever is he at spotting rubies where others with similar titles see only rubble? After three years, it still is too early to tell. But there are clues.

Beathard may have found three fine linebackers everyone else overlooked. But Monte Coleman, Neal Olkewicz and Rich Milot have yet to become certain starters. The Redskins may yet have to invest heavily at linebacker. So far, Mat Mendenhall has not come close to justifying Beathard's choosing him in the second round last year.

Hadn't Beathard promised not to trade a No. 1 draft pick?

"Well," he admitted, "maybe in an old article, one of those throwaway things you guys always write."

He was smiling. Behind their cheery faces, the Redskins were taking serious specific aim at the Rams. They switched No. 1 positions with Los Angeles earlier, and secretly believe the Rams drafting a linebacker from Michigan with questionable potential was a major reason May still was available to them.

They used a second-round choice from the previous deal with the Rams to get Washington. Then the Colts used that choice as partial bait to trade for the rights to Donnell Thompson, a defensive tackle the Redskins would have taken ahead of May had he been available.

The thinking yesterday, in terms of last-minute trading, was more hectic than usual among NFL teams. Beathard's was so confident, so esoteric, as to suggest his moves will prove inspired.Time will determine whether, among general managers, he can sing solo.