MINNEAPOLIS -- Right-hander Kyle Gibson, who has been bothered by lower back stiffness, is likely to be ruled out to start on Saturday against the White Sox.
Gibson saw his scheduled start on Wednesday pushed back until Saturday after suffering back stiffness while throwing his bullpen session on Monday. He played catch on Thursday, but indicated he's likely not going to be ready for Saturday.
"The likelihood of him starting on Saturday isn't very good," Twins manager Ron Gardenhire said. "He did play catch today and is feeling better, but more than likely we'll have to find a starter for Saturday and have him go on like Tuesday."
Left-hander Logan Darnell, who is on the 40-man roster, is considered to be the favorite to be recalled from Triple-A Rochester to make the spot start on Saturday. Darnell, who has a 3.43 ERA in 17 starts at Rochester, last started on Sunday, giving up two runs on six hits over 6 1/3 innings against Norfolk.
Infielder Jorge Polanco, who was recalled from Class A Advanced Fort Myers on Thursday after the Twins traded Kendrys Morales to the Mariners, is likely to be optioned to make room for Saturday's starter.
Rhett Bollinger is a reporter for MLB.com. Read his blog, Bollinger Beat, and follow him on Twitter @RhettBollinger. This story was not subject to the approval of Major League Baseball or its clubs.