Mike Moustakas drove in three runs and Jason Vargas held down the hard-hitting Rockies as the Royals scored a two-game sweep with a 3-2 victory on Wednesday at Kauffman Stadium.

Moustakas cracked a pair of doubles, including one worth three RBIs in the second inning. It was his third two-hit game of the season. His two doubles inflated his season total to seven.

The eight strikeouts from Vargas set a season high. He departed after allowing a two-run homer with two outs in the seventh. Otherwise he mollified baseball’s best offense. The Royals, 20-19, have won six of their last eight since snapping a five-game losing streak last week.

For Moustakas, the breakout came a day after he answered questions about whether he belonged in the major leagues. The team considered demoting him during recent days, before electing to stick with him.

A trio of singles created an opportunity. Lorenzo Cain smacked the third, a hard-hit ball to right field. With hobbled catcher Salvador Perez on second base, third-base coach Dale Sveum didn’t want to risk it.

Into the void stepped Moustakas. He passed on a pair of fastballs from right-hander Jhoulys Chacin. He attacked the third, an 88-mph pitch down the middle. Moustakas cracked the ball into the right-field corner. Cain galloped home from first for the third run.

The Royals jumped to the dugout railing to salute their third baseman. Moustakas got himself thrown out trying to advance to third on a pitch in the dirt. But his teammates stirred to life as he approached. A series of high-fives greeted him as the crowd stood to applaud.