An MRI Thursday night of Troy Tulowitzki's right side revealed a broken rib, according to two major league sources. Tulowitzki is likely facing a lengthy absence. The shortstop exited in the eighth inning of Thursday's 5-4 loss to Washington following a diving stop of a groundball, completing a dizzying parade of injuries to Carlos Gonzalez (bruised left foot) and Dexter Fowler (swollen knuckle on right ring finger). Gonzalez confirmed to The Post that "he was fine, just sore," and Fowler doesn't believe he will miss much time. The concern and uncertainty after the game centered on Tulowitzki, who ranks in the top five in the National League in hitting (.347 average), on-base percentage (.413), home runs (16) and RBIs (51). Tulowitzki was having difficulty breathing after his injury, pointing to a possible rib or intercostal muscle issue. The two-time all-star shortstop has been dealing with soreness in the rib area for a few days, but it wasn't serious enough to prevent him from playing. Because of the torque involved to swing a bat, a serious rib injury could take several weeks to heal before the player is able to play again. Tulowitzki was clearly worried before heading to the hospital, leaving teammates bracing for the worst. "The ribs have been a lingering problem for him. When he came off the field, it was very evident he was done," said manager Walt Weiss, admitting he was concerned about a potential extended absence.