KANSAS CITY -- It had been two weeks and 12 games since the Royals had a starter turn in a quality start. In the middle of a stretch of 20 games in 20 days before the All-Star break, they had worked their bullpen to its brink, and on Sunday, they had multiple relievers unavailable to face the Twins.

They needed a deep start, and Brad Keller knew it. So he gave them one of his best starts of the season.

The 25-year-old allowed two runs in 6 1/3 innings Sunday afternoon, although the offense didn’t provide enough fireworks on the Fourth of July as the Royals lost, 6-2, to the Twins in the series finale at Kauffman Stadium.

“[Manager Mike Matheny] came up to me and was just saying. ‘Hey we got some guys down today, and we might be riding you this game. We’re going to need you,’" Keller said. “That’s what you want as a starter. You want your team to jump on your back and go.”

Keller struck out seven in his first quality start since May 25 against Tampa Bay and his fourth all season. It was the first time a Royals starter threw a quality start since Mike Minor allowed two runs in 6 2/3 innings on June 20 against the Red Sox. Keller’s performance couldn’t have come at a better time for Kansas City and for him. He entered Sunday with a 6.67 ERA in 17 starts.

In those 17 starts, Keller had allowed 66 runs in 81 innings, with 21 of those coming in the first frame (31.8 percent). But Keller needed just 10 pitches to get through the first inning Sunday. He allowed a double that landed just fair down the right-field line, but he then got out of it smoothly with a strikeout and flyout.

Keller’s slider -- a pitch he’s struggled to find consistency with all season but is key to his success -- was lights out Sunday. Of the 24 swings he got on the pitch, 15 of them were whiffs (63 percent). Six of his seven strikeouts came on sliders, with five of those strikeouts inducing a swing-and-miss.

“Felt like I was able to throw it for strikes, bury it in the dirt, get some swing-and-misses on it,” Keller said. “Especially in big situations today. Probably the best I’ve felt with it. I’ve been working on it a lot in my last few starts, sitting back more. I feel like this past month I was really picking up my leg and rushing down the mound, and it was really hard for my hand to get on top of really anything, but especially my slider.

“Today, I really felt like I sat back better, really [was able to] drive the ball to where I wanted to go and get my hand on time.”

Keller is a ground-ball pitcher who thrives on his sinker, and he entered Sunday with a 52.5 percent ground-ball rate in his career. He’s veered away from that approach at times this season, chasing strikeouts instead when he finds himself in binds. But in the series finale, his aggressiveness in the strike zone led to more strikeouts because of the slider -- but also led to weak ground balls.

“I think he’s going to see it’s an ‘and’ proposition to where when he attacks, he’s controlling the strike zone, which then puts him in a position to where he will naturally have more strikeouts,” Matheny said. “Instead of trying to chase the strikeouts from the beginning with marginal pitches or with strike to ball pitches.”

For most of Sunday, Keller looked like the pitcher Kansas City tabbed as its Opening Day starter. And the pitcher that they’ll need as they begin this second half of the season. He wasn’t perfect; Keller walked Miguel Sanó twice after getting into 0-2 counts, and Max Kepler took an inside sinker 395 feet to the Royals' bullpen to give the Twins some insurance in the sixth. He wants and needs to trust his sinker more in the zone, too.

But it was by far the best Keller has looked in the past month.

“I wasn’t completely there today as far as always sitting back and always driving through every single pitch,” Keller said. “It’s a constant work in progress. Definitely a step in the right direction. Felt really good, felt like I had the mechanics rolling on my slider. Got to really feel my fastball a little better and just keep going. Definitely think it’s a building block.”

Kansas City had all the ingredients to go for a sweep at home with Keller’s stellar start, but before it scratched across two runs with two outs in the ninth, the offense was held to just three hits and stifled by Twins starter Kenta Maeda, who struck out 10 in six innings. Minnesota pounced on reliever Richard Lovelady after Keller exited in the seventh for three runs on two homers.