Sean Avery has a lacerated spleen and will be out for the remainder of the season.
The laceration was detected with a CT scan after Avery was taken to hospital directly following Game 3 with the Penguins.
"He's stable and everything is going to be okay," Rangers vice president of public relations and player recruitment John Rosasco told TSN.
Avery suffered the injury during Game 3 but the Rangers are unsure of exactly when it occurred. The winger's pain got continuously worse during the game and became more of an issue when play concluded. Team doctor, Dr. Andrew Feldman, suspected Avery had suffered an injury to his spleen and the pair were driven to hospital. Avery entered the hospital under his own power and checked in between 10:30 pm et and 11pm et.
According to Rosasco, Avery never lost consciousness and never stopped breathing, and his condition was never considered life threatening.
The CT scan detected bleeding and the lacerated spleen and Avery is expected to remain in hospital for the next few days.
The Rangers expect Avery to make a full recovery in the off-season.
The 28-year-old winger played over 14 minutes in the Rangers 5-3 loss to the Penguins on Wednesday. He recorded one assist and had three shots on net.
During the regular season Avery picked up 15 goal and 18 assists, with a plus-6 rating over his 57 games. He has four goals and three assists in eight playoff games.
The bad news did not end with Avery. Both Chris Drury and Blair Betts were injured on Wednesday.
Drury has a torso injury and his status for Game 4 will be determined on Thursday.
Head coach Tom Renney said that Betts has likely suffered a broken jaw after taking a puck in the face on Tuesday night. The team is waiting to see if he will be able to play in Game 4.
The Rangers are down 3-0 to the Penguins in their best-of-seven series. Game 4 goes Thursday in New York.