It's been similar this season, as he's batting .145/.277/.203 from the left side and .263/.417/.342 from the right side. Gardenhire said Hicks has been getting extra work from the right side with hitting coach Tom Brunansky, but that he didn't expect Hicks to make his decision on Monday before the Twins played the Rangers and right-hander Nick Tepesch.
"He's gonna shelve his left-handed swing," Gardenhire said. "He says he has no confidence in it. He's worked at it with Bruno trying to figure these things out. He came to me this morning and said he wants to hit right-handed. So, obviously, when a guy has no confidence left-handed, you gotta do what you gotta do."
Gardenhire said that in an ideal world, Hicks would be optioned to Triple-A Rochester to work on hitting against right-handed pitchers from the right side because he's now lost the platoon advantage. But Sam Fuld remains sidelined with concussion-like symptoms, and Hicks is the only true center fielder on the roster.
"We need him out there," Gardenhire said. "We don't have a replacement right now. He feels confident right-handed, now we're gonna see how he does right-handed. It's just the way it has to be."
Red Sox outfielder Shane Victorino made the same decision to drop switch-hitting last year but he was already in his 10th big league season. Hicks said he made the decision on his own, as the organization never pushed him to drop hitting left-handed.
"Now it's only one side I have to worry about and it's the side I feel confident on," Hicks said. "I've been thinking about it for a while but it was just a decision I felt like making. It's been a combination of a lot of things. For me, I just want to produce and help this team win and I think this is the decision that's going to do that."
Hicks went 2-for-4 in his first game as a full-time right-handed hitter in Minnesota's 7-2 loss to the Rangers. He was also picked off first base in the fifth, and struck out twice.
"It's definitely different," said Hicks, who made the decision to ditch switch-hitting while flying back to Minnesota on Sunday. "It felt good to actually see 'em today. The first at-bat I was letting the ball get too deep. It felt different."
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.