The 42-year-old has yet to make up his mind about returning next season.
New York Yankees general manager Brian Cashman said closer Mariano Rivera informed him earlier this week that he is unsure if he will play again or retire.
Cashman told ESPN New York that on Tuesday he and Rivera had a conversation in which Rivera said he does not know yet if he will return for a 19th season.
"He wasn't certain on what he is going to do," Cashman said.
Rivera, 42, missed a majority of the 2012 season after suffering a torn ACL while shagging batting-practice fly balls in early May. At the time of the injury, Rivera assured the media and fans that he would come back, saying he did not want to end his career with an injury.
Now, however, things are a bit more up in the air. The future first-ballot Hall of Famer just came to the end of his two-year, $30 million contract and negotiations on a new deal could become complicated with Rafael Soriano likely opting out of his contract. Rivera also spent much of his rehab time with his family and could decide it's easier to stay with them rather than return to another long season with the Yankees.