Dylan Cozens' slim chance of making the Buffalo Sabres may be over two months before training camp.

Cozens, the seventh overall pick in the NHL draft last month, underwent "successful" surgery on his left thumb Wednesday and is expected to need two to three months to recover, the Sabres announced Friday.

That timeline makes the 18-year-old center questionable to participate in the start of Sabres training camp and likely further decreases his odds of making the NHL roster. Following Cozens' selection at the draft in Vancouver, General Manager Jason Botterill told the media Cozens would likely need one more junior season before earning a full-time role in Buffalo.

The injury occurred on the final day of Sabres development camp June 29, when Cozens was upended by defenseman Brandon Hickey during his team's first game in the 3-on-3 French Connection Tournament. Cozens took off his glove, revealing his thumb in an unnatural position before leaving for the dressing room in Harborcenter.