New York Mets outfielder Yoenis Cespedes insists he'll be fine after exiting Wednesday's Game 4 of the NLCS because of swelling in his left shoulder.

Cespedes is so sure he'll be healed by the weekend, he's willing to resort to extraordinary measures if he's not.

"I'll be fine by Sunday," he told reporters after the Mets clinched a berth in the World Series with their series-sweeping win over the Chicago Cubs. "If not, I'll chop it off and put a new (arm) on."

Cespedes' second-inning exit came under scrutiny when reports emerged during the game that he had possibly injured his shoulder playing golf in Chicago earlier in the day. The Cuban power-hitter admitted in his postgame comments that he had in fact shot a round of golf, but denied it played a role in his sore shoulder.

"It didn't affect me at all," Cespedes said. "It's been part of my routine. I've played all year long, and I played all last year. It actually helps me with my swing."

Cespedes, who said he's unsure how he suffered the injury, walked and struck out in two plate appearances before exiting in the bottom half of the second. Manager Terry Collins said he expects his slugger to be fully recovered by Tuesday for Game 1 of the World Series.

"(His) shoulder is going to be OK," he said. "They didn't think there was any damage. They thought an injection would calm it down in a day, so he'll be ready. We're going to work out on Friday and I'm sure he'll be ready for that."

Though the Mets did not disclose how Cespedes hurt his shoulder, ESPN's Buster Olney reports the injury occurred during workouts at Wrigley Field. According to Olney, the Cubs' ballpark doesn't have a typical weight room, prompting Cespedes to replace his workout with pushups, which aggravated his AC joint.