Mauer's was a three-run shot in the six-run second inning off Kansas City starter James Shields. Brian Dozier had a leadoff homer for Minnesota.
Starting pitcher Ricky Nolasco had a strong game, going eight innings while striking out four and allowing five hits. Nolasco, a free agent, signed a four-year, $49 million deal with the Twins this winter, the Pioneer Press reports.
The Twins made it two in a row against the Royals, after a 10-1 victory on Friday.
The two teams wind up their series Sunday afternoon at Target Field.