Jennifer, 49, accompanied Alex, 43, to the field where trained the minor league slugger.
The two stood in the backfield as the 23-year-old worked on his batting and other skills.
At one point J. Lo, who showed off her fit figure with a midriff baring jacket, sat mid-field and basked in the sun while the men focused on playing ball.
The lovebirds, who recently celebrated the two year anniversary of their relationship, have been spending a lot of time in Miami.
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