In addition, Chicago called up Dallas Beeler to start the second game. He'll be the 26th man. Beeler also was called up to start in a doubleheader against St. Louis on July 7.
The Cubs were coming off a 13-inning, 5-4 win on Tuesday night that depleted the bullpen. Medina appeared in three games for the Cubs in June, throwing five scoreless innings.
Starter Clayton Richard was designated for assignment. The Cubs got him from Pittsburgh on July 3 for cash, and he went 1-0 with a 5.40 ERA in two starts and one relief appearance.
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