The next phase of Royals rookie left-hander Kris Bubic's learning curve may be as simple as being more aggressive early in the count.

Bubic's fourth career start was similar to his first three in one telling regard: falling behind hitters.

To his credit, Bubic battled, and he gave up just two runs through 4 1/3 innings in the Royals’ 4-1 loss to the Twins on Monday night at Target Field.

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But Bubic entered the game having thrown just 45 percent first-pitch strikes. That percentage won’t improve after he managed 9-of-20 first-pitch strikes on Monday.

“I thought he was good again,” Royals manager Mike Matheny said. “You go five innings and give up two, and one was a solo home run on a pitch that got too much of the plate against a guy who has just been hot. After that, a couple of walks hurt him.

“But he just continues to make good pitches. If you’re going to nitpick, it’s just about getting him deeper into games. How can we keep from having 20-pitch innings? He has special makeup and when it clicks, when he can catch more of the plate and get some quick outs, it’s going to take him to a completely different level.”

Kansas City's No. 7 prospect didn’t throw a first-pitch strike to any of the four hitters he faced in the first inning, and he was fortunate to escape without being nicked for any runs. He fell behind Jorge Polanco, who singled. Bubic then did the same with Mitch Garver, who hit a 99.7-mph rocket that shortstop Adalberto Mondesi fielded to begin a double play. He fell behind Nelson Cruz and eventually walked him. The same scenario unfolded then with Eddie Rosario, who lined out to Mondesi.

“Yes, I am always trying to get ahead,” Bubic said. “It’s been a struggle the last couple of times out. Not getting ahead is going to lead to deeper counts. That’s something we can work on to make my life easier.”

Bubic did grind through the next two scoreless innings with no damage. But the Twins got to him in the fourth. Cruz crushed a middle-in fastball for a home run, his first of two on the night. Cruz now has 29 home runs against the Royals over his career.

Two walks and a two-out RBI single by Byron Buxton made it 2-0 Twins. Bubic avoided further trouble in the fourth, but he left with one out in the fifth.

The 22-year-old lefty, who threw 96 pitches (53 strikes), gave up four hits, walked four and struck out four.

Meanwhile, the Royals’ mostly dormant offense during this four-game series remained that way Monday.

The Royals did have two excellent chances. In the fifth with a runner on first and two outs, Whit Merrifield smoked a liner off the top of the left-field wall but hit it so hard (103.1 mph) that the ball caromed directly on one hop to left fielder Rosario, who threw out Merrifield trying to advance to second base.

“You give us another foot and a half,” Matheny said, “and it’s a tie game there. But then the ball kicks right to the left fielder, custom made, and he makes a perfect throw.”

Added Merrifield: “I thought I hit it out when I hit it. I never hit many balls off the wall that haven’t been a double. Hard off the wall and a perfect throw to second. Sometimes you just tip your hat.”

In the seventh, the Royals had runners at the corners with one out. But Mondesi, now 2 for his last 22, struck out, and Merrifield grounded out sharply up the middle.

Hunter Dozier hit his second homer of the season in the ninth.

Royals catcher Salvador Perez, who was scratched from Sunday’s game because of blurry vision in his left eye, started Monday but exited in the sixth inning. He had visited an eye doctor in Minneapolis on Monday morning who identified a fluid-filled floater on his left eye.

“Midgame he was just having trouble with that spot in the eye getting in the way,” Matheny said. "He felt pretty good early, but then as his at-bats went on he just couldn’t see as he needed to. So we got him out of there.”

Perez was to be reevaluated in Kansas City as the Royals open a five-game homestand.