ANAHEIM -- Starter Brad Keller gave the Royals something they hadn’t had through the first two games of their series against the Angels: A quick inning to begin the ballgame.

Keller set down the top of the Angels' lineup in order on just six pitches, but he could not replicate that success near the tail end of his outing. Keller scuffled in the sixth and was charged with three runs in the frame -- five total -- which ended his night after 5 1/3 innings in the Royals' 6-1 loss at Angel Stadium on Wednesday night.

“That was tough,” Keller said. “The beginning, I felt like I had some of my best stuff fastball-wise. Letting it slip away like that was pretty tough to swallow. Just unfortunate breaks at a time where I felt like I needed to really get deep in the game. ... I felt like throwing six pitches in the first inning or whatever it was, I felt like I was feeling really good about how everything was going, then kind of hit a snag.”

Through his first five innings, Keller gave up two runs and kept the Royals in a one-run ball game despite giving up five hits and walking three.

Royals manager Mike Matheny said Keller showed some of his best stuff, but the start was stained with tough luck in the third and sixth frames.

“I thought he looked great,” Matheny said. “I thought it was one of his best fastballs he's had this year. Really good sync, late action. You could tell by their swings. He was using it on both sides and it had good life to his four-seamer, too. I thought he had some of his best stuff that he's had.”

In the third inning, Keller had Justin Upton down 0-2 in the count with two outs, but walked him and then allowed a single to left field from Shohei Ohtani. He could not strand the duo as they were brought home by Anthony Rendon, who doubled to right field.

Keller walked Jared Walsh and gave up a single to Max Stassi to begin the sixth, and could not work his way out of the jam. Back-to-back one-out RBI hits from José Iglesias and Kean Wong led to Keller’s exit in an inning in which the only out he collected was on a bunt forceout from Taylor Ward.

“I still felt strong,” Keller said. “I still felt like I had some good stuff. I think I just left too many balls up. That was one thing. Going back and looking at some of the video, by driving the ball down a little bit better, maybe [the] results are different. … Like I said, just gotta be better than that.”

The Royals did not lead at any point during the series. The last time Kansas City led a ballgame was the start of the sixth inning in Saturday's 5-4 loss to the Twins.

Matheny said a bright spot from the series was Keller’s ability to provide some length after leaning on the bullpen to pitch 11 1/3 innings over the first two games.

"We needed a strong start, because of the shape of our bullpen, and Brad came out and gave us that start," Matheny said. "Just lost a little control with the sixth.”