A magnetic resonance imaging exam performed Friday revealed a slight tear of the meniscus cartilage in Rodriguez's right knee, Yankees Manager Joe Girardi said.
"He's being evaluated and we should probably make a decision (Saturday) on the course of action," Girardi said. "The two courses are: You play through it and get (surgery) at the end of the year, or you have the surgery and see how long he misses."
Girardi said the decision will rest mainly with Rodriguez, who wasn't in the lineup for Friday's rained-out game against Tampa Bay.
Surgery would likely sideline the slugger for a month.
Rodriguez is batting .295 with 13 homers and 52 RBI in 80 games so far this season.
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