On the online player card, there is the section that displays all the detailed stats splits for the current season (vs Lefty, vs Righty, RISP, etc). One of the split categories is Spring Training. But these splits don't appear until after spring training has completed.
This seems a little backwards: on March 23rd (when you are very interested in seeing the player's spring training stats), you can't view the spring training stats on the online player card. But in August (at a time when you could care less about their spring training stats), the spring training stats are available.
Player Report for #76 Bryan Maag