Walker underwent tests on his left knee after he was removed from Tuesday's Grapefruit League game against the Nationals, and the Cardinals are expected to provide an update on his status later Wednesday, John Denton of MLB.com reports.

EDGE Analysis

Walker tweaked his knee when he stepped on a sprinkler head while pursuing a flyball in the second inning of Tuesday's contest. The Cardinals classified his injury as left knee discomfort after he exited the game, but a formal diagnosis should be provided once his tests results are in.