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.
What do you think of Jennifer joining Alex at the ballpark? Let us know in the comments.