Yankees position players are scheduled to arrive in Tampa on Wednesday, with their first day of workouts scheduled for Thursday. Rodriguez was already working out on Monday after undergoing a physical exam, according to The New York Times.
The Times reports that Rodriguez's early appearance "seemed to catch the team by surprise."
New York general manager Brian Cashman has said that Rodriguez will be the team's designated hitter this season, but Rodriguez was taking grounders at both third base and shortstop on Monday, according to reporters.
Rodriguez is coming off of a year-long suspension for performance-enhancing drugs and has not played in a major league game since Sept. 25, 2013.
Last week, he wrote a handwritten apology letter to fans, saying he takes "full responsibility for the mistakes that led to my suspension for the 2014 season."
Rodriguez, who turns 40 in July, has played for the Yankees since 2004. He won a World Series with New York in 2009 and was named the American League MVP in 2005 and 2007. - Molly Geary
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