New York Mets relief pitcher Francisco Rodriguez (75) throws in...

New York Mets relief pitcher Francisco Rodriguez (75) throws in the bottom of the ninth inning against the New York Yankees. (June 18, 2010) Credit: Christopher Pasatieri

HOUSTON - As promised, the Major League Baseball Players Association Wednesday filed a grievance on behalf of Mets closer Francisco Rodriguez challenging both his placement on the disqualified list and the team's decision to convert his contract from guaranteed to non-guaranteed.

A source familiar with the union's position said that the Players Association is "confident" it will eventually recoup every bit of the money the Mets are withholding from Rodriguez. He is due about $3 million for the rest of this season, $11.5 million for 2011 and has a vesting option for $17.5 million with a $3.5-million buyout for 2012.

The matter ultimately will be decided by baseball's arbitrator unless a settlement is reached.

In a news release, the union said: "Because the grievance alleges material breaches of Francisco's contract [including nonpayment of salary], the Basic Agreement requires that the matter be processed expeditiously. No hearing date has been set."

The Mets responded to the union's release with the following statement: "We disagree with the position of the Players Association. We believe our action was justified and appropriate."

The Mets announced their actions against Rodriguez on Tuesday after he underwent surgery to repair a torn ligament in his right thumb. The Mets claim Rodriguez told a team trainer he suffered the injury during the Aug. 11 incident in which he allegedly assaulted his fiancee's father and was arrested at Citi Field. The union hasn't said if it will dispute that.

However, the source said, "He hasn't said that's when it happened. That's what management is saying. It's a he-said, she-said thing at this point."

Rodriguez, who the Mets say did not tell them about the injury until Sunday, was suspended for two games after his arrest. If the union's grievance is successful, that will be the only punishment the Mets will be able to impose on Rodriguez and his contract will revert to fully guaranteed.