Borussia Dortmund head coach Nuri Şahin said an "extremely sad" Giovanni Reyna will miss the team's Bundesliga match against Heidenheim on Friday and that the United States international is set to be out for "a few weeks."

Reyna missed both of the USMNT's matches during the international break after suffering a groin injury.

"Gio Reyna will be out; he has picked up an injury with the national team," Şahin told a news conference on Wednesday. Schlotti [Nico Schlotterbeck] is suspended. Everything else should be OK. That would mean that Serhou [Guirassy] will be involved."

The winger played just 280 minutes in the league for Dortmund in the first half of last season and a further 235 for Nottingham Forest following a loan move in January.

"He came straight back [from the national team] and I found him extremely sad; unfortunately, it will take a few weeks. And then I hope that he can continue on this good path afterwards," Şahin said.

Reyna, son of former U.S. captain Claudio, has played 10 minutes during Dortmund's first two Bundesliga games this season.

Mauricio Pochettino was confirmed as the new head coach of the USMNT on Tuesday. The Argentine signed a two-year contract that will see him lead the team in the 2026 World Cup, which the U.S. is co-hosting with Canada and Mexico.