Cubs shortstop Starlin Castro was pulled from a game against St. Louis shortly after making a mental mistake that let the Cardinals score a run.
The play came in the top of the fifth inning at Wrigley Field on Saturday. Castro was taken out to start the sixth.
The Cardinals led 1-0 and had the bases loaded with one out when Castro caught a popup by Matt Carpenter in short left field. Castro put his head down and hesitated to throw home, looking as if he thought the inning was over.
Jon Jay scored from third base and the other runners advanced.
Donnie Murphy switched from third base to shortstop to replace Castro in the sixth, and Cody Ransom came off the bench to play third.