Rodriguez, 37, underwent surgery on his left hip on Jan. 16 and was initially expected to miss approximately six months.
Cashman, though optimistic A-Rod will return as planned, is prepared for the "chance" the third baseman isn't able to suit up at all this summer.
"Yeah," Cashman told WFAN, when asked if there was a chance of missing the entire season. "I think because [of] the serious nature of the surgery and the condition that he's trying to recover from, you know, there is that chance."
Rodriguez hit .272 with 18 homers and 57 RBIs during the regular season last year, but struggled in the postseason. The three-time American League Most Valuable Player Award winner was just 3-for-25 (.120) in postseason play, including 0-for-18 with 12 strikeouts against right-handed pitchers. He was lifted for a pinch-hitter on multiple occasions before eventually being replaced in the starting lineup.
Earlier this offseason, the Yankees signed veteran third baseman Kevin Youkilis to a one-year, $12 million contract to replace Rodriguez while he recovers from the injury. Youkilis hit .235 with 19 home runs and 60 RBIs in 122 combined games with the Red Sox and White Sox last season.