NEW YORK -- A-Rod has left the building.

Alex Rodriguez stormed out of his own grievance hearing Wednesday after arbitrator Fredric Horowitz ruled that commissioner Bud Selig did not have to testify before the embattled slugger's attorneys.

Rodriguez slammed his hand on a table at Major League Baseball's Manhattan Park Avenue offices and cursed at MLB chief operating officer Rob Manfred, a source with knowledge of the proceedings told ESPNNewYork.com.

Horowitz was in the midst of the 12th day of hearings Wednesday on the grievance filed by the players' association to overturn the 211-game suspension given to the New York Yankees third baseman by MLB last summer for alleged violations of the sport's drug agreement and labor contract.

"This is ridiculous!" Rodriguez is said to have shouted after Horowitz issued his ruling shortly before noon.

Rodriguez then pointed a finger at Manfred, who directed MLB's investigation into the since-shuttered Biogenesis clinic suspected of being a source of illegal performance-enhancing drugs for ballplayers, and said "This is f---ing bulls---!" Another source said earlier that Rodriguez cursed directly at Manfred.

Rodriguez attorneys David Cornwell and Jordan Siev remained in the hearing room and entered into the record that they believe the hearing is "an unfair process," according to a source.

It was unclear whether the hearing will continue.

After walking out, Rodriguez issued a statement through his spokesman.

"I am disgusted with this abusive process, designed to ensure that the player fails," the statement said. "I have sat through 10 days of testimony by felons and liars, sitting quietly through every minute, trying to respect the league and the process. This morning, after Bud Selig refused to come in and testify about his rationale for the unprecedented and totally baseless punishment he hit me with, the arbitrator selected by MLB and the players' association refused to order Selig to come in and face me.