Freeman felt the discomfort after throwing an inning of relief on Monday for the Surprise Saguaros. The Cardinals, as a precaution, opted to shut down the left-hander. Farm director John Vuch said hat the issue is not considered serious.
Freeman will need about seven to 10 days of rest, meaning that it's unlikely he'll make another AFL appearance, since the season concludes on Nov. 15. In seven AFL outings, Freeman allowed six runs (three earned) and 11 hits in seven innings.
Wong, the Cardinals' top pick in the 2011 First-Year Player Draft, is hitting. 321 in 13 AFL games. He has scored eight runs and driven in 10 for the Saguaros, the first-place club in the AFL West.
The Rising Stars Game will be played on Saturday, with MLB Network set to televise the contest. First pitch is scheduled for 7 p.m. CT.
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.