Hicks remained in the game after the play despite a visit to center field from Twins manager Ron Gardenhire and trainer Tony Leo, but he was replaced by a pinch-hitter in the seventh inning.
Gardenhire said Hicks was still dealing with concussion-like symptoms on Friday, so they decided to put him on the DL.
"He's the same as last night," Gardenhire said. "It was one of those shaky moments where he took a good whack against the wall out there. So we put him on that seven-day concussion DL, and we'll let him get well. This is something you don't mess with."
With the Twins playing 21 innings on Thursday, they decided to add an arm to their bullpen and went with Darnell, who is expected to pitch in long relief.
Darnell, who was originally drafted by the Twins in the sixth round of the 2010 First-Year Player Draft, made four starts for Triple-A Rochester, posting a 1.69 ERA with 21 strikeouts and seven walks.
"He was starting down there and was throwing the ball well," Gardenhire said. "We need innings. We have to have a guy up here that's stretched out. He can throw 100 pitches if we need it."
Darnell was in uniform and ready to pitch against the Orioles on Friday, as his turn in the rotation was scheduled to come on Saturday with Rochester. He said he woke up after midnight with several missed calls and texts from Triple-A manager Gene Glynn, Twins assistant general manager Rob Antony and Twins traveling secretary Mike Herman to tell him he was getting called up for the first time in his career.
"It's definitely exciting," Darnell said. "It's something you always look forward to as a baseball player. When you're young you look forward to it, and when you're in the Minors you're always pushing to get there."
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.