The Bullets will try to win Washington's first professional world championship since Franklin Roosevelt was president when they meet the Seattle SuperSonics tonight for the National Basketball Association title.

The last time Washington fans had a chance to celebrate the ultimate pro triumph was 1942, when Sammy Baugh and the Redskins defeated the Chicago Bears for the NFL crown, 14-6. None of the current Bullet players had been born at that time.

Team owner Abe Pollin has been pursuing a championship for his franchise since 1964, when the club was in Baltimore. Twice before, the Bullets have gotten to the final round, only to lose, 4-0, both times.

The Bullets enter the 9 p.m. contest (WTOP-TV-9. WMAR-TV-2, WDCA-TV-20. WTOP-AM-1500) tied at three games apiece with the SuperSonics in this best-of-seven championship series. The Sonics, who have won 22 straight at Seattle Coliseum, are five-point favorites.

But Washington players were telling anyone who would listen yesterday that home-court advantage means little at this stage of the series. Motivation, they claimed, was more important.

"If we play with the same intensity that we played with on Sunday (in game six) we won't worry about home-court advantage," said forward Elvin Hayes, who has been trying to win an NBA title for 10 years. "By now, you don't hear the crowd. You just worry about how you are playing."

The Bullets have recent history on their side. Four of the last five NBA champions have won the deciding game on their opponents' court. The only exception was last year, when the Trail Blazers wrapped up the crown in Portland by nosing out Philadelphia.

But the Bullets' chances of becoming the eighth team to win the league title in the last nine years will depend on the continued improvement of Kevin Grevey's sprained left wrist.

Grevey, who played only six minutes Sunday because of the injury, shot well in practice yesterday but did not dribble with his left hand. He said afterward that his wrist felt "110 percent better than it did after the last game.

"I've got a lot of motion and it's flexible and it feels free. It's still sore but a lot of guys have sore spots this time of the season."

Coach Dick Motta said he was "90 percent sure Kevin will start, if he doesn't fall off the bed tonight. He looked a lot better out there."

If Grevey does not play well at the start of the game, Motta said he would go first with Charles Johnson "and if he can't handle the defensive job (on Dennis Johnson), we'll go with Bobby Dandridge."

Dandridge played at guard Sunday mainly to defend against Johnson. But he also was able to score from the backcourt. "I don't like guard, but at this point, you do what you can to help the club," he said.

Of course, the Bullets have learned to overcome injuries all season. They've made it this far without star guard Phil Chenier, who has been out since January with a bad back, and they've won playoff games without Wes Unseld (ankle), Dandridge (neck) and Grevey (various ailments).

The injuries contributed heavily to what was an unpredictable campaign. When it began, Motta said his club would be among the league's "elite teams," but the Bullets would up struggling to finish third in the Eastern Conference after losing out to San Antonio in the race for the Central Division title.

Not much was expected of them in the play-offs, but Motta told his players prior to the Atlanta miniseries, "You are just inches away from being a championship team. It's up to you to close the gap. I told the older guys that time was running out for them and I told the younger guys that the opportunity for them might be running out."

Washington is hoping that those older players, especially its front line of Unseld, Hayes and Dandridge, which has 29 years of NBA experience, will hold up under the intense pressure tonight better than Seattle's younger athletes.

"I know I'm excited, I really am," the usually unemotional Unself said yesterday. "This is an opportunity and I'd like to take advantage of it. We all do."

The Washington team, which began in 1961 as the Chicago Packers franchise before a 10-year stay in Baltimore and the move to landover in 1973, didn't win a game in its previous two trips to the finals. The Bullets were shut out, 4-0, by Milwaukee in 1971 and by Golden State in 1975.

But they broke that jinx by winning game two of this series. And they proved they could win in Seattle in game four, which was played in the massive Kingdome. The last time the Sonics lost in the Coliseum was Feb. 8, to the Bullets.

"We could have wrapped up this series already, said Motta, remembering that his club lost a 19-point lead in the opening game and couldn't win game three at Capital Centre. "We've been scrambling, but now things are finally where they should be. This will be the first real pressure playoff game. Both clubs will feel it."

This has been an unpredictable series. Both teams have lost substantial leads, they've lost home games they were favored to win, they've had star players come up with poor efforts and they've had unexpectedly good performances from second-line players.

Until the Bullets trampled the Sonics by 35 points Sunday, no game in the series had been decided by more than eight points. Seattle players maintain the game six embarrassment will have no effect on them; the Bullets say the runnaway has done wonders for them.

"Our key in winning that game was rebounding and defense," said Dandridge. "Wes and Elvin took over inside right from the beginning. Then we could run and do what we wanted to do on offense.

"Our defense hasn't been that sharp, but it looked better. They couldn't get all the shots they wanted."

Seattle has gotten the bulk of its points from back-court stars Dennis Johnson, Fred Brown and Gus Williams. But the Sonics have been most potent when Brown has run off strings of baskets and Paul Silas, the wily veteran, has complemented his rebounding with scoring.

Silas, who has been successful defending the taller Hayes, especially in the fourth period, did not score in either of the Sonics' last two losses in the series. Brown's shooting has been inconsistent, but it was his long-range marksmanship that was responsible for Seattle coming back in game one and breaking away in game five.

Dennis Johnson, who did not play well Sunday, has held the Sonics together with his fine shooting and defense against the Bullet guards.

Washington has been trying to run all series, but until Unseld and Hayes overwhelmed Marvin Webster, Jack Sikma and Silas on the boards Sunday, Seattle had been able to stop the Bullets from getting into a fast-paced game.

To win, Motta and his players realize they must have to receive help from their bench, which has contributed substantially in only two games in the series, both Bullet wins.

With Grevey's status uncertain, the reserves loom even more important.Moving Dandridge to guard will work only if Mitch Kupchak or Greg Ballard produce as they did Sunday, when the Substitutes outplayed Seattle's reserves.

"If we can get good games out of the bench and out of our experienced people like Elvin and Bobby, we'll be okay," said Motta.

"It will be interesting to see how Seattle reacts to the game. This is the first time they've been faced with no tomorrow. Before, we let them off the hook early by losing the first game and they knew if they lost one game, they'd still be around.

"Now those open shots won't be quite as easy to make. The basket gets smaller. It's hard to say how either club is going to react.

"But just remember. We got behind in this series and drug ourselves back. Now things are different. We've done surprising things before, so why not again?"