Shuhei Kojima hurt his right leg (calf area) when he ran out a grounder to short in the fifth inning. He was removed from the game as a precaution. He did not go to the hospital and was treated with ice.
Source: Sports Hochi 3/31/2017
[UPDATE 4/2 @ 12:21am]
Kojima was taken off the active roster on April 1 with a strain in his right calf.
Source: Sanspo 4/1/2017