HOUSTON — Shawn Chacon was put on waivers today by the Houston Astros, a day after he got into a physical altercation with general manager Ed Wade.

If another team doesn't claim Chacon by Monday, the Astros say they will release the pitcher and terminate his contract for cause, which would set off a confrontation with the players' association over the nearly $1 million that would remain on Chacon's contract.

"Based on the information we have to date, we believe the Astros' response violates the Basic Agreement," union general counsel Michael Weiner said. "If Shawn Chacon clears waivers and is released, we will pursue appropriate relief on his behalf."

If Chacon is released Monday, $983,607 of his $2 million salary would be in dispute. The union also could claim lost bonus opportunities for the pitcher, who has $1 million in available performance bonuses in his deal, starting with 130 innings and ending with 210 innings.

Houston says Chacon violated a provision in the uniform player contract that states the player may be terminated if he shall "fail, refuse, or neglect to conform his personal conduct to the standards of good citizenship and good sportsmanship or to keep himself in first-class physical condition or to obey to the club's training rules."

Chacon's agent, Dan Horwits, said he would wait to see if his client clear waivers before he addresses whether a grievance would be filed.

"As the process unfolds there will be more facts revealed which will shed more light on the situation," Horwits said. "By no means does that mean the physical confrontation was appropriate, and Shawn knows that."

Wade said the problems began when he asked manager Cecil Cooper to call Chacon into a meeting to discuss media reports that he was asking for a trade because he was unhappy with being bumped from the rotation.

After Chacon refused Cooper's repeated requests to come to his office for the meeting, Wade went into the team dining room to try to get him to meet.

After he said he wanted to speak in the dining room, things became heated.

"I did not raise my voice to the player, curse the player," Wade said. "I did not make any defamatory remarks toward the player. Chacon responded with profane and threatening remarks and got up from his seat. He moved in front of me until we were chest to chest and then he shoved me to the ground. When I attempted to get to my feet, he shoved me a second time. At this point players and coaches intervened."

Wade said this wasn't the first problem with Chacon. He said he ignored pitching coach Dewey Robinson when he asked him to throw a bullpen session during Tuesday's game. He said he had also ignored Robinson when he approached him during the first inning of a game June 1 at Milwaukee.

Wade said Cooper followed Chacon to the clubhouse to "settle him down" during that game, but instead had to pull him from the game. Chacon was fined for that incident.

"As an organization we believe that we have fairly treated this player," Wade said. "His pattern of disrespect and defiance to me, to the manager, the pitching coach and most importantly the organization led us to this decision."

Chacon is 2-3 with a 5.04 ERA in 15 starts and 85 2-3 innings for Houston this year. The right-hander set a major league record for a starting pitcher with nine straight no-decisions to open the season.

Astros owner Drayton McLane said he spoke to baseball commissioner Bud Selig on Thursday and Selig supports the position the team has taken.

"It's very disappointing," McLane said of the altercation. "Our goal has always been to be very accountable and very responsible."

AP Baseball Writer Ronald Blum in New York contributed to this report.