New York Yankees pitcher Domingo Germán has been placed on administrative leave by Major League Baseball as part of the Joint MLB-MLBPA Domestic Violence Policy.

The league announced the decision Thursday in a statement:

The Office of the Commissioner of Baseball announced today that New York Yankees pitcher Domingo Germán has been placed on Administrative Leave under the Joint MLB-MLBPA Domestic Violence Policy. Per the policy, the initial period of Administrative Leave may last up to seven days, barring an extension.

Major League Baseball’s Department of Investigations has commenced an investigation into the matter that led to his placement on Administrative Leave. MLB will have no further comment until the investigation is complete.

MLB didn’t release details about what led to the investigation, but sources told Yahoo Sports that German had a physical altercation with his girlfriend late Monday/early Tuesday at a party.

It was reported to MLB by a witness on Tuesday morning. That witness was not employed by MLB, according to the same source. It is unknown if video of the alleged assault exists or if MLB is attempting to acquire video.

Lindsey Adler from The Athletic says no police report was filed.

No police report regarding Domingo Germán, per league sources. The incident was reported directly to MLB on Tuesday and a preliminary investigation was expedited. Germán is not allowed to be around the team while on administrative leave. — Lindsey Adler (@lindseyadler) September 19, 2019

The Yankees, meanwhile, released a statement saying they support the league’s investigation.

“We fully support all measures being undertaken by the Commissioner’s Office pursuant to the Policy on Domestic Violence. We support this policy which reinforces that domestic violence has no place in our society and cannot be tolerated. We have followed the lead of Major League Baseball and will continue to provide our complete cooperation throughout the investigative process. We reserve any further comment until the investigation reaches its conclusion. All questions pertaining to this matter should be directed to the Office of the Commissioner.”

While the investigation is still ongoing, the Yankees do not expect German to be part of their postseason plans at this point, sources tell Yahoo Sports. The Yankees clinched the AL East with a victory against the Angels on Thursday.

Germán, 26, is in his third season with the Yankees and has been one of their most successful pitchers this season. He has an 18-4 record with a 4.03 ERA. The team is currently one win away from clinching the AL East title and Germán figured to be an important postseason contributor.

While it’s possible he returns to the team in seven days when his time on the restricted list ends, it’s not likely. Most players that Major League Baseball has put on the restricted list during a domestic violence investigation have usually had their leave extended or eventually been suspended by the league.

Prior to being placed on administrative leave, German appeared in the Yankees’ 3-2 loss to the Angels on Wednesday night, throwing 2.1 scoreless innings.

Yankees manager Aaron Boone said he heard Wednesday that Major League Baseball was conducting an investigation, but said he could not say whether he knew prior to using German, and was unsure if German knew.

“Because it’s a Major League Baseball issue and we’re kind of in a stand-down mode,” Boone said regarding not being able to comment on when he heard.

Boone and Yankees general manager Brian Cashman planned to address the team prior to Thursday’s series finale.

“Set baseball aside, this is a bigger issue obviously and something that’s — when you hear the words domestic violence, it’s one of those things that stops you in your tracks,” Boone said. “We just want to be part of it and I give Major League Baseball and the Players Association credit for doing their part several years ago trying to get ahead of this and putting disciplinary action in place to hopefully being a part of the solution to what is a problem in our society, obviously.”

Boone acknowledged this will affect his team’s postseason plans.

“There’s no denying the importance of Domingo to our team. There is that element of we must continue on and continue to press forward but it’s also — this is something that touches our society, unfortunately,” Boone said. “Hopefully (the team meeting) is a forum for people or players to talk through it and have comments or questions or whatever and there’s no script you go off for it. As best you can, deal with it, handle it, and offer the right kind of support.”

Yahoo Sports’ Tim Brown and Matt Ehalt contributed to this story.

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