Reynolds has looked comfortable at first base, though, even making a key play on Tuesday night that led to an inning-ending double play.
After center fielder Ben Revere grounded out to first, Reynolds fired home to cut down Twins infielder Luke Hughes, getting him caught in a run down as he tried to score.
"That was a big play there in a lot of ways looking back on it," Orioles manager Buck Showalter said. "Mark made sure he got that out [at first] and still had another out there.
"I know coaching third base, that's a tough play for a runner and a third-base coach. If you go directly to the plate you're probably out. If you wait too long... it's a tough one. We were fortunate it was hit in the right place and worked out for us."
Reynolds has become the Orioles' everyday first baseman since Chris Davis has been sidelined since Aug. 14 due to a partially torn labrum in his right shoulder.
With Reynolds at first, Robert Andino has taken over as the No. 1 option at third base, and Ryan Adams is now the Orioles' everyday second baseman. Those three, along with J.J. Hardy at shortstop, have provided solid infield defense this week at Target Field.
"Robert's handled third base well in two games, and I felt confident he would," Showalter said. "So far so good. Obviously defense is a big part of being able to sustain some things over the course of a season."