The NFL Players Assn. has become involved in Quincy Carter’s release by the Dallas Cowboys.

The union filed a grievance over the release Aug. 4 of the quarterback, who started all 16 games and one playoff contest for the Cowboys last season, claiming the team had violated the collective bargaining agreement in releasing him.

“You don’t go from being a starting, playoff quarterback in this league to someone not good enough to make the 80-man roster the next summer,” Richard Berthelsen, the union’s general counsel, said in a statement.

The case would be heard by professor Stephen Burbank of the University of Pennsylvania Law School. The union said the first step probably would be taking depositions from Cowboys owner Jerry Jones and coach Bill Parcells.

The team has not given a reason for Carter’s release, although there were widespread reports that he had failed a drug test. Parcells and Jones have been vague publicly, but the owner has said he was willing to discuss the reasons with the league or the players association.

Carter’s agent, Eugene Parker, said his client was approached by the union about filing the grievance. Carter supports the action, but his focus remains on playing.

“It’s in the players association’s hands. They’re handling it,” Parker said. “It’s not on Quincy’s mind.”

The CBA does not permit teams to administer drug tests, although if Carter already was in the league’s drug program by virtue of a previous positive test, he could be tested by the league.

Patriots

New England signed tight end Benjamin Watson, the last choice of the first round. Watson signed Monday after firing his agent, Tom Condon, last week, and hiring Pat Dye Jr. Watson had held out for two weeks.

Dolphins

Miami signed 32-year-old wide receiver Antonio Freeman on Monday. Freeman had 14 catches last season for Green Bay.

Bears

Offensive tackle John Tait, who signed a six-year, $33.6 million deal to leave Kansas City and come to Chicago, returned to drills after sitting out a week. The 6-foot-6, 315-pound Tait sought a specialist’s opinion on a strained right groin. Satisfied that it was nothing more serious, he resumed practicing.

Colts

Wide receiver Aaron Moorehead sat out of Monday’s workouts because of a shoulder injury.

Falcons

Will Overstreet was placed on injured reserve, the third straight year the defensive end’s season has ended early because of a shoulder injury.

Raiders

Offensive lineman Robert Gallery, the Oakland Raiders’ top draft pick chosen No. 2 overall, went down because of a right elbow injury during practice. X-rays were negative.

Broncos

The Denver Broncos waived cornerback Reggie Stephens on Monday, five days after he left camp without giving a reason.