The Washington Bullets may not have the services of Bob Dandridge when they play their first exhibition game of the season tonight against the New Jersey Nets in New Haven, Conn.

Dandridge took a hard fall and banged his head on the floor in Friday night's practice and was unable to work out yesterday morning because of a headache.

The major change for the Bullets this year is in the starting backcourt, where Kevin Porter and Roger Phegley have replaced free-agents Tom Henderson and Kevin Grevey. Henderson is now with the Houston Rockets and Grevey, who signed a new Bullet contract three days ago, is currently playing behind Phegley.

Phegley and Porter will be joined in the starting lineup tonight by center Wes Unseld and forwards Elvin Hayes and either Dandridge or Greg Ballard.

The Bullets still have 17 players on their roster, but only 14 are healthy and will make the trip. The injured players -- all with back ailments -- are veterans Mitch Kupchak and Phil Chenier and rookie Steve Malovic.

"The veterans will probably get a half game in," Bullet Coach Dick Motta said. "We want to have a good look at the young kids mainly. There will be free substitution. We're going to take 14 guys up there and they'll all play."

Three rookies -- Garcia Hopkins, Charlie Floyd and Norman Black -- and one free agent newcomer, Gus Bailey, are among the 14 making the trip.

With the playing status of Chenier uncertain this season, Bailey, a 6-foot-5 four year NBA veteran, has become an important man in training camp.

"He's some pretty good insurance for us," Motta said. "We knew what he could do all along. He's a veteran and it shows. He's not a great shooter, but he's in the Dennis Johnson category defensively."

The Nets are led by high-scoring guard John Williamson, forward Bernard King and rookie forwards Calvin Natt of Northeast Louisiana and Clif Robinson of Southern California, the seventh and 11th players picked in the draft.