During his offense’s recent slump, Twins manager Rocco Baldelli has said that he’d look for somebody in his lineup to come out with a big game and pick up the rest of the lineup.

How about one big swing?

Minnesota hadn’t done much with the scoring opportunities amid its skid entering Monday night’s series opener in Milwaukee. Eddie Rosario turned that around in the third inning, when he crushed a center-cut changeup for his fourth career grand slam. That was all the support right-hander Randy Dobnak needed as the rookie pitched the Twins to a 4-2 win at Miller Park, snapping a four-game losing streak, and placing himself as baseball's qualified ERA leader.

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“Obviously, we were all waiting for that clutch hit,” Rosario said. “Luckily, I was able to connect tonight. I was talking to some of my teammates, not to keep our heads down, work together as a group, as a unit. We have younger players, and just trying to keep the morale up. I think I was able to do that today. And I’ve done it before. We had a bad series in Kansas City, but that’s over, and we got the win tonight.”

Rosario’s grand slam, the Twins’ second of the season, wasn’t some miracle cure-all for Minnesota’s recent offensive slide. The Bomba Squad was still held scoreless in the game’s eight other innings and only mustered two hits beyond the third inning, after all. Still, it was an important moment in which Minnesota took advantage of a chance to swing momentum and did enough to win a game -- something absent in its recent sweep by the Royals.

“I’m sure a lot of the guys feel like we needed it,” Baldelli said. “There are no do-or-die games at this point in the season, but it’s something that’s definitely, definitely necessary for that. … I think those big moments actually kind of lend themselves to everyone kind of relaxing even more going forward and that definitely helps them when they step on the field.”

Alex Avila led off that third-inning rally with a single to center, and after Max Kepler also singled, Jorge Polanco popped a ball into foul territory that Christian Yelich initially caught before it popped out of his glove. A replay review ruled no catch, giving Polanco another chance to move the runner to third. He did, and Milwaukee starter Adrian Houser plunked Nelson Cruz before Rosario smashed the first pitch he saw an estimated 402 feet to right-center to cash in all four runs.

As it turns out, Houser’s first-pitch changeup played right into Rosario’s approach this season of staying back on such pitches.

“I hit, in the last couple of days, two line drives to left-center,” Rosario said. “I want to stay there. In the first at-bat, I hit a little fly ball to left field. I don’t try to change that approach. But I want to start early. When I see the pitch, I see it really big. I see a really slow one, but I stay on the ball. This year, I feel really comfortable when hitting changeups.”

Dobnak made it stand. The rookie still owns the lowest ERA among qualified starters in the Majors (0.90) after he allowed one run on four hits in five innings against the struggling Milwaukee offense. The only blemish on his ledger was a two-out RBI double in the second inning by Orlando Arcia that hit off the wall and just out of reach of a leaping Rosario.

The 25-year-old Dobnak has allowed two runs in 20 innings across his first four starts this season.

Dobnak started off a little wild, with a four-pitch walk to his first hitter of the game, in part because his sinker had too much depth to it -- something he’s had to adjust to this year. He learned to just trust the movement on the pitch and let it fly, and after throwing 42 pitches over his first two innings, he needed only 37 to get through the next three.

At the start of last season, Dobnak was pitching for Class A Advanced Fort Myers. And now here he is, the Majors’ ERA leader, ending losing streaks. What would he have thought of this storyline had someone presented it to him last year?

"I probably would have called them crazy, but I trust myself every time I go out there,” Dobnak said. “I have 100 percent confidence in myself to pitch to the best of my ability and give the team a chance to win. That's what I'm going to do every time I go out there, no matter whether I'm facing the Brewers or the Pirates or the Yankees. I'm going to go out there with the most confidence in the world and just do my thing."