Given the choice to risk further injury or play it safe with Max Scherzer, the Washington Nationals picked the latter Tuesday, placing their ace on the 10-day injured list with groin inflammation, the move backdated to Saturday. To fill his roster spot, the Nationals promoted right-handed reliever Justin Miller from Class AAA Rochester. To make room for Miller on the 40-man roster, they designated Rochester starter Rogelio Armenteros for assignment.

“After going through the process, I just want to be more cautious than not,” Manager Dave Martinez said. “And this is an injury that, right now, it’s getting better. So we want it to completely get better. It’s something that we don’t want him to reinjure with the fact that we’re going to force him to try to pitch.”

Scherzer tweaked his groin against the San Francisco Giants on Friday. On Monday, he told reporters he wouldn’t be able to face the Pittsburgh Pirates on Wednesday, his next scheduled turn in the rotation. There was a chance he would stay off the IL and face the first-place New York Mets this weekend. Instead, he will hope to return by next Tuesday, when the Nationals visit the Philadelphia Phillies.

That’s the earliest he could take the mound. The Nationals will start Paolo Espino on Wednesday and have Jefry Rodriguez ready behind him. Before Scherzer could rejoin the roster, they have two games with the Pirates, rest Thursday, have four games in three days with the Mets — including Saturday’s split doubleheader — and rest again Monday.

The off days could help untangle the Nationals’ complicated pitching plans. The upcoming rotation could be Patrick Corbin on Tuesday, Espino on Wednesday, Erick Fedde on Friday, Joe Ross and Jon Lester for the doubleheader, then Corbin for Sunday’s series finale.

Washington is now without Scherzer, Stephen Strasburg (10-day IL with nerve irritation in his neck), Daniel Hudson (10-day IL with elbow inflammation), Austin Voth (10-day IL with a fractured nose) and Will Harris (60-day IL with right hand inflammation). Voth faced batters in a simulated game Tuesday and can come off the IL on Friday. Otherwise, the bullpen is an unforeseen mix of Brad Hand, Tanner Rainey, Kyle Finnegan, Wander Suero, Sam Clay, Kyle McGowin, Espino, Rodriguez and Miller, who signed a minor league deal this spring and wasn’t invited to big league camp.

Miller’s last pitch in the majors was for the Nationals on May 17, 2019. He missed the rest of that a season with shoulder and back injuries. Before that, in 2018, he finished with a 3.61 ERA in 52⅓ innings. That was more than enough to earn a spot in the next year’s bullpen. He just couldn’t stay healthy.

And because of that, Miller signed a minor league deal with the Toronto Blue Jays in 2020 and didn’t make the Opening Day roster. He spent the summer at their alternate site in Rochester, facing the same hitters on loop, before he was traded to the Cincinnati Reds. Then he was back in Rochester this spring, pitching for the Class AAA Red Wings. He had a 0.55 ERA in 16⅓ innings when his phone rang Monday night.

He was called up to the last team to give him a shot. He had to catch a plane.

“I had to do a lot of work to get back here, prove to some people that I could still do it,” Miller said with a smile Tuesday, leaning against the Nationals’ dugout. “So it was nice to do that.”

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