Deduno (2-1) baffled the Royals on four hits over six innings, walking two while striking out five. The right-hander, making his third start since being recalled May 24 from Class AAA Rochester, threw 62-of-105 pitches for strikes.
Ryan Doumit socked a solo homer and added a run-scoring single to spark the Twins' offense.
Luis Mendoza (1-3) yielded three runs on seven hits over 4 1/3 innings for the Royals, who fell for the 11th time in 13 games.
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