Gaborik said Friday he was injured during Game 3 of New York's first-round playoff victory over the Ottawa Senators when he was hit into the boards shoulder-first.
Gaborik, who scored 41 goals during the regular season, didn't miss any games because of the injury but he was limited to just five goals and six assists during New York's 20-game post-season run that ended in the Eastern Conference finals.
"I tried not to think about it," Gaborik said Friday during a conference call. "I don't want to make excuses, but it was there."
Gaborik will have the operation on Wednesday in New York, according to a statement issued by the Rangers. This was the first time the right winger played an entire season without missing a game.
Earlier this week, Rangers general manager Glen Sather said 14 players were scheduled for appointments with doctors. Gaborik will be hard-pressed to be ready in time for the start of next season, which is slated for October.
The five-month projection would put his return around November.
"I'm going to try everything to be back before," Gaborik said.
Gaborik also had a team-high 76 points in the regular season. He was benched during Game 2 of the East finals against New Jersey, and Gaborik said his injury wasn't a factor in his playing time being cut.
Gaborik, who had only one goal against the Devils, felt weakness in his shoulder, which took away power from his shot.
"I am obviously frustrated," he said. "I knew I wasn't OK. I was hoping for better from the doctors. I just have to focus on getting back healthy and ready to go.
"I know I could play better. I don't think it was affecting me that much. It was just weak. My shot wasn't there."
With the top-seeded Rangers just one round away from reaching the Stanley Cup finals, Gaborik didn't consider sitting out to rest his shoulder or go for surgery then. He is still looking for his first NHL championship.
"I tried to put it aside and focus on playing," Gaborik said. "You don't get too many situations where you can play for the Cup. A lot of guys were banged up. We tried not to think about it just go out and do our best."