Mike Moustakas hit the brakes at second base and pounded his hands together. A wave of adulation and revulsion washed over him.

The majority of the fans at Busch Stadium jeered a result that sank their Cardinals. The smattering of Royals fans called out the nickname of Moustakas, who thumped a two-run, seventh-inning double in a 6-0 victory on Monday.

“The results were good,” Moustakas said. “The best part about it was we got two runs out of it.”

The noise melded into one, the night’s loudest reaction in an otherwise brisk, tidy affair. Moustakas recorded his first hit since returning from the minor leagues. He followed a solo home run for Alex Gordon as the Royals tagged St. Louis starter Shelby Miller for a three-run inning.

Danny Duffy, 3-5, rebounded from his last, sluggish outing with six sharp innings. He held the Cardinals scoreless, struck out five and allowed only two men on base. His fastball displayed more life, and his case of dead arm appeared to dog him for only one appearance.

With Duffy dealing, the offense capitalized on a series of Cardinal mistakes to avoid a repeat of the previous day’s shutdown at the hands of Toronto starter Mark Buehrle.

Miller lost the handle on two wild pitches in the seventh, putting two runners in scoring position for Moustakas. St. Louis outfielder Randal Grichuk overran a Salvador Perez single in the eighth, an error that opened the door for another three-run inning. In victory, the Royals gave gave evidence of their potential when their most pressing flaw, an inconsistent offense, does not hound them.

On Thursday, the team reassigned Pedro Grifol and installed Dale Sveum as their new hitting coach. The maneuvers had yet to alter the team’s reality: They still entered Monday’s game ranked last in the American League in on-base plus slugging percentage, runs and home runs.