"I MADE A MISTAKE leaving a great job in Washington," said George Allen to the press. That's one way of putting it.Mr. Allen was fired as head coach of the Los Angeles Rams by owner Carroll Rosenbloom after two defeats in pre-season games. Mr. Rosenbloom had the nerve to believe that a person who buys a team should have some say in its operation. Mr. Allen, as we know, is of a different persuasion - which is how he came to leave his great job here.

Of course, Mr. Rosenbloom had no business being surprised at Mr. Allen's performance. A foolish consistency has been Mr. Allen's hobgoblin lo these many years, and only a dreamer or a pighead would have failed to foretell that old George was going to run the Rams just as he had run the Redskins just as he had run the Rams before them. Mr. Allen's mistake in this affair was not in being himself, but in losing. Had the Rams not dropped their latest game 17 to 0 to San Diego, Mr. Rosenbloom might have had to suffer an agonizing reappraisal, but would probably have let bygones be bygones - at least through the season's opener.

Ah well. "Winning isn't everything; it's the only thing," as the late, canonized Vince Lombardi said - thereby at once inventing the negative tautology and providing sportscasters with a maxim by which to live. Still, given that, is it too much to expect some of these big-time club owners to behave a little less capriciously? Hire George Allen in the winter, fire him in the summer. Fire Billy Martin in the summer, rehire him two years hence. Does anyone here remember Earl L. (Curly) Lambeau? Redskins owner George Preston Marshall had all the faith in the world in Curly, but fired him during the exhibition season nevertheless, after a shoving match in a Sacramento hotel.

Then there was Charlie O. Finley, beloved owner of the then Kansas City A's, who in 1961 described his Joe Gordon as "manager of the year" 12 days before giving Joe the axe. That was shortly after Joe was swapped, manager for manager, with Jimmy Dykes of the Detroit Tigers.

How these owners carry on. Some odds-player amony them is probably on the horn to Mr. Allen right now, saying, George, we need a winner.