BOSTON -- Alex Rodriguez confirmed early on Monday that his representatives are in the process of filing a grievance against the Yankees for mishandling his medical treatment dating back to last year's postseason.

According to the player, Rodriguez's lawyers contacted the Major League Baseball Players Association earlier this month to formally begin the grievance process. The development was first reported by ESPN New York.

"I believe we have filed that process," Rodriguez said after the Yankees' 9-6 victory over the Red Sox. "You have to check with the union, because they're the ones that are responsible for actually filing that. But yes, it is in process."

Rodriguez's confirmation of a grievance came after his attorney, Joe Tacopina, told The New York Times that he believed the Yankees concealed MRI results and knowingly played Rodriguez during the postseason with a torn left hip labrum during the American League Division Series and AL Championship Series.

In claims denied by both Yankees president Randy Levine and general manager Brian Cashman, Tacopina told the Times that the Yankees "rolled him out there like an invalid and made him look like he was finished as a ballplayer."

"I was pretty bad, you have to admit," Rodriguez said.

Hours after Cashman stated that he no longer feels comfortable talking to Rodriguez because they are in a "litigious environment," Rodriguez said that it has presented a "very challenging situation" to be at odds with Yankees management while simultaneously wearing their uniform and trying to help them win games.

"It's been a war," Rodriguez said. "It's been very tough."

Regarding Rodriguez's claims of playing injured during the postseason, manager Joe Girardi has said that he did not know Rodriguez was injured until the slugger himself mentioned a problem with his hip during Game 3 of the ALDS.

"I found out about 10-12 days later, after Detroit, that I had a big hole in my left hip," Rodriguez said. "Dr. [Marc] Philippon said I needed to have immediate surgery. So that's that.

"The MRI is the MRI. I had a big hole in my left labrum. I'm just telling you what the doctors were saying."

The MRI is a point of contention between Rodriguez and the Yankees. Cashman reiterated on Sunday that Rodriguez had complained to the Yankees about a sensation of not being able to "fire" with his surgically repaired right hip, not his left, while struggling in the ALDS.

An MRI on the right hip showed no damage, so Rodriguez continued to play, even lobbying Girardi to keep him in the lineup. Rodriguez eventually had a procedure to repair the labrum, a hip impingement, remove a cyst and insert five stabilizing anchors.

"Listen, all I can tell you is what you already know," Cashman said. "The medical records are factual. If [they] have a dispute with the medical records, we are very comfortable with the business we've gone about."

After stating earlier on Sunday that he was not ready to discuss the Times article, Rodriguez said postgame that he was aware of Tacopina's comments and would not dispute the attorney's claims.

"I'm having such a hard time just focusing on playing every day," Rodriguez said. "What my lawyer says, he said. I'm going to stand behind it."

Rodriguez said that he believes his teammates have "rallied around" him while his ordeal plays out. He also expressed hope that he and the Yankees can one day be at peace, and that Rodriguez eventually will be able to reconcile with both Levine and Cashman.

"Look, I love this team. I love the fans of New York City," Rodriguez said. "This is a very complicated situation, but we're doing the best we can."