Among the Twins' many miseries last year was their incompetence in doubleheaders. They played four of them, going 0-8 in those games.

On Saturday, they really needed that story line to change against the Royals at Target Field. This was a job for the D&D Boys -- Scott Diamond and Cole De Vries.

Those two pitchers began the year at Class AAA Rochester, but they have helped patch some of the gaping holes in the Twins rotation.

Diamond pitched eight strong innings again, as the Twins cruised to a 7-2 victory in Game 1, and De Vries was sharp for six innings as the Twins defeated the Royals 5-1 in Game 2.

It was the Twins' first doubleheader sweep since Sept. 13, 2008, when they took two at Baltimore.

How was De Vries rewarded? The Twins sent him right back to Rochester after the second game. Manager Ron Gardenhire explained that De Vries wouldn't have been ready to pitch again for four or five days, and the team is only eight days from the All-Star break.

A new rule this year allows teams to add a 26th man for doubleheaders, so after getting that promotion last week, De Vries figured this stint would be short.

"It's really frustrating, but coming here I basically knew I was the 26th guy," he said. "Obviously, I would love to stay up longer, but I knew the situation at hand, so nothing really surprised me."

De Vries (2-1) got his first taste of the big leagues in late May and made three starts, going five innings each time, defeating these same Royals on June 4, but never really proving he was ready for a permanent rotation spot. For the Eden Prairie native, pitching in front of his hometown fans only intensified things. But he looked a lot more confident this time, holding Kansas City to one run on five hits, with one walk and six strikeouts.

"It was night and day," De Vries said. "First couple times out there, emotions were very high. Tonight I felt a lot more comfortable out there."

The Twins gave De Vries some early breathing room by hitting three home runs in the first three innings off Royals starter Luke Hochevar (5-8). Josh Willingham hit a two-out, two-run shot in the first inning, giving him 16 homers for the season, matching Trevor Plouffe for the team lead after Plouffe homered in the opener.

Chris Parmelee, who has been idling on the bench, hit his first homer of the season leading off the second inning, and Joe Mauer lined an opposite-field homer in the third.

The Twins were wearing Minneapolis Millers throwback uniforms in Game 2, and the three-homer outburst must have been a tribute to Joe Hauser, who hit a then-record 69 homers for the Millers in 1933.

"The ball's been flying here, with the temperatures like they have been," Gardenhire said. "There's been a lot of home runs at this ballpark; you just have to hit them."

With the ball carrying on a hot day, Diamond and De Vries did a good job keeping pitches in the ballpark. Kansas City's only home run of the day came in the second inning of Game 2, when Billy Butler sent a blast into the second deck in left field, an estimated 423 from home plate. Later that inning, the Royals had runners on second and third with one out, but De Vries struck out Jarrod Dyson to end an 11-pitch battle, then fanned Alcides Escobar with a 73-miles-per-hour breaking ball.

"Cole De Vries was outstanding," Gardenhire said. "I think he came up and did exactly what we were hoping he would do. He got us deep into the game and pitched really well."

Before Game 1, Gardenhire had the expected concerns about how his pitching would hold up through the doubleheader. He joked that all he needed was a complete game from Diamond.

The lefthander nearly delivered, going eight innings, just as he did in last Sunday's win at Cincinnati.

"I really think I wouldn't have been able to go eight if it wasn't for our defense," said Diamond, who improved to 7-3 with a 2.62 ERA.