"Patrick Sharp underwent an emergent surgical appendectomy this evening after experiencing some abnormal abdominal discomfort," team doctor Michael Terry said in a statement. "The surgery was successful and I anticipate a full recovery in approximately three to four weeks."
Blackhawks training camp opens Saturday and the regular season starts on Oct. 7. Depending on Sharp's recovery time, he could miss the beginning of the season.
Sharp, an assistant captain, led the Hawks with 34 goals and produced a career-high 71 points last season despite suffering a left knee injury in late March. He returned to the lineup ahead of schedule, missing just seven games.
Sharp plays in all important situations, including on the power-play and penalty-killing units.
Jesse Rogers covers the Blackhawks for ESPNChicago.com and ESPN 1000.