Washington Nationals’ lineup for series opener with the Philadelphia Phillies...

Washington Nationals’ skipper Davey Martinez talked after Wednesday night’s loss to the St. Louis Cardinals about the rough night rookie shortstop Carter Kieboom had in the field and at the plate.

“You’re seeing a young, 21-year-old kid playing in the major leagues,” Martinez explained.

“The game sometimes — you come up here, the game speeds up on you a little bit, we’ve just got to get him to slow down, relax, and play the game the way he’s been playing his whole life, but he’s got to just let the game kind of come to him, slow down a little bit, the game is speeding up on him a little bit right now, but he’s going to be fine.”

Kieboom, a 2016 1st Round pick, who had a .379/.506/.636 line, six doubles, three homers, 16 walks, and 20 Ks in 18 games and 83 plate appearances at Triple-A Fresno before he got the call, was 3 for 12 with two home runs in his first three games, but he went hitless in the next three, 0 for 10, with four Ks. He said he didn’t think the game was speeding up on him.

“I don’t feel like it’s going too fast at all, I do feel comfortable out there,” Kieboom said after an 0 for 3 game in which he struck out twice and took a walk. He did, however, add that he wasn’t lacking in confidence in his abilities after a few tough games.

“I know what I’m capable of doing,” Kieboom said. “I know I can hit. I know I can play defense. It’s not a matter of me having confidence.

“I know I can do all those things, it’s just one of those things where baseball is a crazy game where you can be the man on the moon for a while, and then next thing you know it’s like you haven’t swung a bat before. It’s all part of the game. I’ll treat this like any other situation. I’ve been through this before, obviously not up here, but I’ve been through this before, it’s the same thing, it’s the same game, I’ll make the adjustments, and I’ll get it right.”

Martinez decided to give the infielder a breather in the series finale with the Cards.

“I talked to him this morning. I had a great conversation with him,” the manager explained, as quoted by MASN’s Byron Kerr.

“I told him we’re just going to give you a little mental break today. We assured that he is doing fine. He’s 21. I told him, ‘You’re 21, you made the major leagues, that’s pretty impressive.’ He wanted to get some work in with [first base/infield coach Tim] Bogar today and he’s going to go hit and I said he will be right back in there tomorrow. And if we need you sometime today be ready because you’ll definitely be used. We’ll still give him a little day.”

Kieboom did get a pinch hit appearance on Thursday, striking out late in what ended up a 2-1, sweep-avoiding win for the Nationals, who’d dropped the previous three to the Cardinals.

Kieboom is back in the lineup tonight for series opener with the Philadelphia Phillies in the City of Brotherly Love. Still no Juan Soto though, after he was scratched from each of the last two with back spasms.

HERE’S THE NATIONALS’ LINEUP FOR THE 1ST OF 3 WITH THE PHILLIES: