Diamond apparently took him seriously, pitching eight solid innings, and Trevor Plouffe homered to help the Twins beat the Royals 7-2 in the opener of a day-night set Saturday.
"You ask me what you want," Gardenhire said, "you want a complete game by your starter. That's pretty close. A heck of a performance."
Easily the Twins' most-effective starter since being called up in May, Diamond (7-3) allowed two runs and six hits to give Minnesota a big lift with another game coming up. Twins relievers entered with the third-most innings (268 1/3) in the majors behind the Royals (283 1/3) and Colorado (284 2/3).
"I was feeling confident earlier, this is just icing on the cake I guess," Diamond said. "I'm pretty happy to be able to just keep going out. With a double header today, I'm just trying to eat up as many innings as possible."
Diamond struck out four and walked two while pitching eight innings for the second consecutive start. Glen Perkins finished the seven-hitter. It was a far cry from Friday's loss to the Royals, in which Minnesota needed five innings of relief from its bullpen.
Royals left-hander Jonathan Sanchez (1-4) didn't fare nearly as well. While Diamond cruised through Kansas City's lineup, Sanchez issued six walks and was done after 4 1/3 innings. His 10 allowed hits tied a career high.
"At times when you're fighting your command, your whole focus and concentration is trying to get the ball over the plate," Royals manager Ned Yost said. "There were times when his whole focus was this way that he forgot about what was happening behind him."
Both starters finished with 101 pitches.
Minnesota strung together five consecutive hits to open a 6-0 lead in the fifth inning, including a strange RBI single from Brian Dozier.
With one out and runners on first and second, Dozier's grounder bounced off the ground behind the batter's box -- and then rolled fair. While Sanchez and catcher Brayan Pena scrambled after the ball, Dozier sprinted safely to first and Ryan Doumit scored all the way from second.
"It was spinning really, really hard, so I was just like, `Well, why not, I'm dying for a hit, let's just take off and see what happens," Dozier said with a laugh. "(Justin Morneau) of course was the first one, he said, `Hey why don't you just try that every time, you might get a hit out of it."
The Royals won't remember that play quite as fondly.
"It was clearly a foul ball," Pena said. "Then I saw it spinning back and I saw that it was a fair ball. It's one of those games where things don't go your way."
Yuniesky Betancourt drove in Kansas City's first run with a groundout in the sixth. He also singled in a run in the eighth.
Sanchez pitched five effective innings to win at the Los Angeles Angels in his first start of the season on April 8, but has struggled since that victory. He is 0-4 with a 7.19 ERA in his last nine starts.
"It's a slump, you know," Sanchez said. "It's not working. I'm not doing anything that's working right now."
The loss snapped Kansas City's four-game winning streak. ... The Twins won a doubleheader game for the first time at Target Field since May 8, 2010 against Baltimore. They were swept each of the last three times since. ... The doubleheader is to make up an April 28 rainout. ... Casilla had his fifth three-hit game of the season. ... Game 2 of Saturday's doubleheader will feature Minnesota's Cole DeVries against Luke Hochevar.