After playing basketball for the last 16 years with hardly a day's break, Kevin Grevey finally discovered an easy way to improve his game. He stopped practicing.

A hamstring pull forced the Bullet guard to stay away from workouts for almost a week before he returned yesterday to play what he admitted was "one of my best games in a long time."

A relaxed and rested Grevey pumped in 22 points as Washington romped to a 122-105 triumph over the defenseless New York Knicks at Capital Centre. He said afterward the last few days "have really taught me a lesson."

"This is the longest vacation I've taken away from basketball ever," he said. "But now I feel really good, the best this year. I tried to come back to soon, I realize that now. You rest these things and they clear up. You don't, and they can stay with you."

Grevey first hurt the hamstring 10 days ago against Chicago. He was advised not to play against Seattle Tuesday night, but did and aggravated the injury.

"I could have been out two more weeks," he said, shaking his head. "But it was our biggest game of the year and I was told we were going to have a sellout. I should have stayed out."

While the Bullets were on a two-game road trip, Grevey drove to Baltimore for two-a-day treatments. He watched on television as his teammates split those contests despite having problems with opponents' big guards. Then he decided to try out the leg before yesterday's game, "just to see if it would respond."

It did. He didn't have any pain during the game and moved as free and easily as he has in a month. And the Bullets likewise ran and shot with the kind of authority that they haven't shown consistently since the first of the year.

With Grevey in the lineup, Coach Dick Motta could go back to his regular substitution system. New York couldn't cope with that kind of depth, especially since the Knicks hardly wasted time playing defense during much of the afternoon.

"Kevin makes a difference with our offense and defense," said Motta. "He got a couple of rebounds and they can't use their guards inside as much. And we could run our baseline plays again for him."

The Bullets wasted little time taking control. They opened a 10-point first-quarter lead behind 10 points from Bob Dandridge, eight from Grevey and six each from Elvin Hayes and Wes Unseld.

As long as the Knicks got balanced scoring, they were able to stay in contention the rest of the half. But Bob McAdoo began dominating the offense after intermission and his one-man show couldn't match Washington's firepower.

McAdoo, who finished with 34 points, recorded 13 in the third period, but his team saw a seven-point deficit increased to 15 by the end of those 12 minutes.

"I really didn't remember concentrating on defense that much against them," said Bullet forward Mitch Kupchak. "They just got the ball up the court and shot it. Against Seattle or Atlanta, they work for a shot and you have to think at both ends."

The Bullets, however, were playing a thinking man's game. Their erratic fast break regained efficiency -- "We have to push the ball like that to win," said Dandridge -- and they worked the ball inside consistently against the Knick front-court players.

The result was the kind of balanced scoring that highlights most impressive Washington victories. Along with Grevey's 22 (on seven of 12 shooting). Dandridge had 24 (eight of 13, Hayes 20 and Kupchak 15.

"Now we have to work a little harder on our defense and I think we'll be back where we should be," said Dandridge. "New York really wasn't doing much to stop us. I thought it was pretty easy for us to go inside, and when we do that, we are going to win."

The Knicks, who improved immediately after Red Holzman replaced Willis Reed as coach, now have lost five in a row. Marvin Webster, who Hayes yesterday called "an average center who needs some players around him," is being lost in the maze of one-on-one plays and multiple substitutions -- at one point yesterday the Knicks tried to put six players on court.

"They've got their problems but I'm sure Red will work them out," said Motta. "This is the third time this year we've played them and they looked different each time."

Motta was more concerned about his team. He had hoped to be 20 games above.500 by the end of January and could come within one win (against Atlanta Tuesday at Capital Centre) of that goal before the Bullets embark on an eight-game road trip that will take most of February.

He also has to keep an eye on Kupchak, who has been fighting a strained Achilles tendon for almost a week. Again yesterday, Kupchak almost decided not to play, but did after being assured by the team doctor "that he had never seen a tendon snap with this kind of injury."

"I just want to make it to the All-Star break (Saturday) and then I'll have some rest," he said. "It doesn't feel right, but as long as I can't hurt it by playing, I'll keep going. I'm sure the rest will do me good."

Just ask Kevin Grevey.