This is the kind of luck the Washington Bullets are having lately with injuries. Mitch Kupchak finally produced his first outstanding game tonight since returning from an Achilles' tendon injury, only to be knocked out again with back spasms in the fourth quarter.

Kupchak's latest ailment, which he said probably would sideline him for a couple of days, was the only negative aspect in the Bullets' 117-114 triumph over the Cleveland Cavaliers.

But the victory couldn't stop Coach Dick Motta from wondering what curse has struck his club. He had bee waiting for two weeks for Kupchak to come around after battling the tendon problem and now he has to wonder how long the back condition will sideline his supersub.

Kupchak popped in 19 points, making eight of 11 attempts, to keep Washington in the game until Bob Dandridge and Elvin Hayes, with an able assist from Tom Henderson, could pull out the win in the fourth period.

"It was great to see Mitch look good, and then he has to come up with the back," said Motta. "It doesn't seem right."

Kupchak, who said he has had similar spasms before, was forced out of the game with 3:39 left, just after scoring his seventh point of the last period.

He left with the Bullets trailing, 107-106. But Dandridge scored seven points down the stretch and Henderson added two free throws and an assist on a Wes Unseld layup to subdue the Cavaliers, who play Washington again Sunday at 1:45 p.m. at Capital Centre.

Dandridge finished with 24 points, including 11 in the final 12 minutes. Hayes scored 31, including seven in the fourth.

Henderson, playing his first game in a week after spraining an ankle, proved his value to the Bullets. He picked up 12 assists in 32 minutes and made sure the club executed its offense near the end, something it has not been doing well lately.

With Washington ahead, 113-112, Henderson was stalling away the clock at the top of the key as Motta yelled to him to keep it until Cleveland fouled. But Henderson spotted Unseld free under the basket for an easy layup with eight seconds left to wrap up the triumph.

"I felt good playing again," said Henderson, "although the rest did me good, too. We executed pretty well at the end. I was going tc let them foul me but I saw Wes so I figured why not take the layup.

"But what was good about this one was Mitch's play. It was nice to see him back into it again. Clevland was clogging the middle and so I told Mitch to shoot from the outside. They had to come out after that, and it helped Bobby and Elvin."

Kupchak didn't feel he was in a slump the last two weeks -- "My shooting hasn't been mental. I really felt they were all going to go in" -- but he admitted he has been pressing the last few games, trying to regain his touch.

"It's a fact of life for me that if I'm not scoring, I don't play well," he said. "I needed this game, it felt real good. But looking back at those other games, I just couldn't believe I haven't been playing better. I've felt healthy.

"I just can't be too upset about this back-spasm thing. I've had them before and it usually takes a couple of days for me to come around."

Kupchak's scoring took up the slack for another subpar game from the back court. The Bullet guards contributed only 21 points, making nine of 27 shots after a 14-for-43 effort in a loss to Milwaukee Friday, when Kupchak also did not shoot well.

Until the final minutes, it appeared that Cleveland rookie Butch Lee was going to singlehandedly pull out the game. He tossed in 13 points in the fourth, working against both Henderson and Charles Johnson, with his final basket giving the cavs their last lead, 112-110.

Then Dandridge converted two foul shots. Lee missed a jumper and Dandridge was hacked again. He hit one of two shots. Bingo Smith couldn't score at the other end and that led to Unseld's layup.

This was Washington's 46th victory of the season, leaving the Bullets four games short of wrapping up the Atlantic Division title.

"I was pleased with how we played," said Motta. "Tommy is our glue; he keeps us together. And we executed the way we have to."

The the team flew back to Washington on a charter to await another meeting with Cleveland in less than 16 hours.