Alcides Escobar went 3-for-4 with a run-scoring single for Kansas City, which clinched its three-game, home-opening series against Minnesota.
Jeremy Guthrie (2-0) earned the victory despite surrendering four runs on six hits over 6 2/3 innings, walking one and striking out two.
Tim Collins tossed a scoreless eighth and Greg Holland collected his second save as the Royals improved to 5-3 for the season.
Pelfrey lasted only two innings, yielding six runs on eight hits in absorbing the loss.
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