KANSAS CITY -- It happens to the game’s best pitchers. And now it has happened to Royals rookie right-hander Brady Singer for the first time in the big leagues -- he didn’t have his best stuff.

Singer, on the heels of two dominant starts, was out of whack Tuesday against St. Louis at Kauffman Stadium in a 5-0 loss. With the defeat, the Royals officially were eliminated from postseason contention.

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Singer walked a career-high five and also hit a batter. He gave up three hits and three runs before manager Mike Matheny took him out for righty Jake Newberry. Singer threw 81 pitches and only 44 for strikes.

Interestingly, after Matheny’s mound visit to replace Singer, Matheny got into it with home-plate umpire Manny Gonzalez and was quickly ejected. It was Matheny's first ejection as Royals skipper and his 16th as a manager -- and this one came on his 50th birthday.

Singer and Matheny were not pleased with what they perceived was a tight strike zone.

“I walked off the field and I basically told [Gonzalez] I thought he was squeezing the kid,” Matheny said, “and he made it harder for the kid than he needed to. And he didn’t reply. And then he asked who [the reliever] was and I told him ‘Figure it out for yourself.’

“That’s about how that whole thing went. I can’t really tell you what happened after that.”

Singer said he had an exchange with Gonzalez as he was leaving the mound prior to Matheny and Gonzalez getting into it.

“Yeah, I did. Absolutely,” Singer said.

Care to share what was said?

“Um, no,” Singer said.

Matheny said he was unaware that Singer had an exchange with Gonzalez.

“No, or I would have been thrown out sooner than that,” Matheny said.

Regardless, Singer’s command seemed off almost immediately. After two quick outs in the first inning, Singer walked two hitters before striking out Yadier Molina to end the threat.

“I got the first two batters out and felt I was commanding the ball,” Singer said. “But then they were spitting on some good pitches. ... I tried to get ahead in the count, but I wasn’t getting some of the borderline calls.

“[The strike zone] seemed pretty tight. I don’t know why.”

Singer wasn’t so fortunate in the second. He walked the first two hitters, then hung a slider to Dylan Carlson (who was hitting .170 entering Tuesday), who drilled a two-run double. Kolten Wong later singled to score Carlson.

After a scoreless third inning, Singer again hung a slider to Carlson, who promptly tripled to right, ending Singer’s night.

The Royals got a scare in the sixth when reliever Kyle Zimmer, who came into the game with a 1.23 ERA, left with a 1-2 count on Carlson. Zimmer seemed to be trying to squeeze the baseball between pitches, perhaps hoping to get a feel for the ball.

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Earlier this season, Zimmer experienced a “zinger” -- what Matheny described then as a feeling of electricity suddenly surging down the arm that sometimes causes temporary numbness or tingling.

“So far, everything has come back pretty clean,” Matheny said after the game. “Not much different than the zinger he had before but in a different spot. [The trainers] feel pretty good about it but we’re going to be really cautious about it going forward.”