Greenwood Just Going Along for the Ride : Eastern Conference: After an injury in camp, he has had to watch Detroit’s drive for a second NBA title from the Pistons’ bench.

The rubber band around the wrist is symbolic of being a Detroit Piston reserve, not of the way his career is being held together.

David Greenwood, who has been nothing but an everyday player since attending Verbum Dei High School and UCLA in the late 1970s, says he has two or three years left in the battered twine that passes for his Achilles’ tendons. Whether it will be in Detroit, he can’t say. Neither can the Pistons.

His everyday role now, when not practicing, is to sit on the end of the bench, often dreaming of playing. Gaze too far into that land of make-believe, though, and regret it. One of the other have-nots in the Pistons’ eight-man rotation--Scott Hastings, William Bedford and Gerald Henderson--will make it a painful wakeup call to reality.

“That’s what the rubber bands are for,” Greenwood explains. “It’s something one of the guys came up with to keep us in the game. We have so many easy wins. It’ll be like, ‘Oh, well, we’re up by 15.’ You’ll see Hastings’ eyes start to wander around the crowd or something. One of us will reach over, grab the rubber band--and pow! “

Just one of the ways this season has been painful for Greenwood, who signed a one-year contract for a reported $600,000 just before training camp.

After having averaged 72.3 games in his first 10 years in the NBA with Chicago, San Antonio and Denver, he made only 37 appearances in 1989-90, the fewest of any Piston on roster all season.

Greenwood broke double-figure minutes five times. He may play in the summer pro league at Loyola Marymount for the first time, mostly against unknown players trying to earn a contract and rookies. Heading into Game 4 of the Eastern Conference finals against the Bulls today at Chicago Stadium, he has played twice in the playoffs.

“Mentally, it has been difficult,” said Greenwood, who lives in San Antonio but is considering a move back to Los Angeles with his wife and two children during the summer. “It’s been difficult sitting and seeing the other guys play and seeing that I know I can do what is happening on the court.

“I don’t regret coming here. I thought it was a great choice when I signed, and I still do.”

There’s the trade off, though: a very good chance at a championship ring. For that opportunity, next year can wait.

“Most players will tell you that the greatest thing is winning a championship and stuff like that,” he said. “But it would be even better if you’re an integral part of all that. That’s what means the most. I’ve had a wonderful time here, but I wish I could have contributed more to what has happened.”

What the 6-foot-9, 225-pounder has contributed, to be exact, is 60 points and 78 rebounds. Brought in as a big-man replacement for Rick Mahorn, lost to Minnesota in the expansion draft after last season, he has been unable to crack the eight-man rotation, a hamstring injury during camp slowing his adaptation to the Pistons from the start.

More recently, Greenwood, who turned 33 Sunday, was clued in that Coach Chuck Daly has a reputation for spots being earned over time.

“This team is built on loyalty,” Greenwood said. “They like to go with the guys who’ve got them here. James Edwards told me he went through the same thing at first, but that it gets easier next year.”

If there is a next year in Detroit for the free-agent-to-be. There have been three operations on the left Achilles’ tendon and two on his right to reach this point, crediting Los Angeles-based Dr. Tony Daly for much of his current improved condition. He hasn’t come back from so much to spend the last years of the game using those ankles for nothing more than sock holders.

“We know it’s been tough on him,” General Manager Jack McCloskey said. “But he has showed us a lot. If it were a different person, character-wise, they could have caused us a lot of trouble by complaining in a similar situation. David has got a great deal of character.”

Just not much playing time.

“It’s been a real pleasure to be here,” Greenwood says. “I haven’t achieved any personal goals, but I’ve had some wonderful times.”

Notes

Dumb statement from a reporter to Dennis Rodman, whose Pistons lead the best-of-seven series, 2-1, after losing Saturday: “There doesn’t seem to be a sense of panic around this team.”. . . Game 5 will be Wednesday at Auburn Hills, Mich.