The Kansas City are shuffling their rotation.
Out is right-hander Jeremy Guthrie, who is 8-7 with a 5.65 ERA and a 1.57 WHIP in 23 starts. In six starts since the All-Star break, Guthrie has a 6.48 ERA and 1.80 WHIP. He will move to the bullpen.
Taking his place will be right-hander Kris Medlen, who has a 2.51 ERA in seven relief appearances. He has struck out 14 batters in 14 1/3 innings.
"We want to find out what we have with Kris Medlen," manager Ned Yost told MLB.com. "We know what we have with Chris Young and we know what we have with Jeremy Guthrie. While there's time left, we want to find out what we have with Medlen."
Medlen missed the 2014 season after recovering from his second Tommy John surgery. In 2013 with the Atlanta Braves, he won 15 games and posted a 3.11 ERA in 32 games (31 starts).
Medlen will start Monday against the Baltimore Orioles.