TUKWILA, Wash. — The list of injured Seattle Sounders somehow doesn’t seem to be getting any shorter with each passing week. The latest player to join that group is Léo Chú, who missed Tuesday’s training session while getting treated for a foot injury he suffered in the 2-1 loss to Sporting KC.

Chú likely would have been in a position to start Wednesday’s U.S. Open Cup match against the LA Galaxy, but is now deemed questionable. Either way, he was not going to play in Saturday’s regular-season match against the Houston Dynamo due to his wife being scheduled to give birth to the couple’s first child.

Also newly unavailable to the Sounders is Obed Vargas, who has left the team to join the United States ahead of the U-20 World Cup. The tournament was recently moved to Argentina and will run from May 20-June 11.

The Sounders were already going to be without Nouhou (malaria), Cristian Roldan (concussion protocol), Raúl Ruidíaz (hamstring) and Kelyn Rowe (knee). As a result, the Open Cup lineup will likely look very similar to the reserve-heavy group that started against San Diego Loyal in the previous round.

“We’ll put out a strong lineup, but more importantly we’ll put out a strong effort,” Sounders head coach Brian Schmetzer said. “When you’re hamstrung with injuries to key guys, you do what you can, but the one underlying thing that binds that whole group is they put in the effort. I can guarantee that.”

Heavy Defiance presence

Although the Sounders will take more than 30 players on the trip to Southern California, Schmetzer said he declined several veterans’ requests to play against the Galaxy. Wednesday’s gameday roster could include as many as seven players on short-term contracts from the Defiance.

Cody Baker, Eythor Bjørgolfsson, Antonio Herrera, Georgi Minoungou, Paul Rothrock, Travian Sousa and Hal Uderitz were all training with the Sounders on Tuesday.

One normal starter who will likely be available at least off the bench is João Paulo, who missed the Sounders’ previous game while serving a yellow-card suspension.

“He might see some minutes,” Schmetzer said about the Brazilian.

What might the Galaxy do?

The Galaxy’s season is not going as anyone seemed to plan. With just six points through 10 games they sit 28th in the 29-team league, with one of those losses coming against the Sounders earlier this year. In addition to the Open Cup being a possible avenue toward turning around their season, the Galaxy also have an additional day of rest than the Sounders both leading into this game and coming out of it.

That could influence Greg Vanney’s lineup decision.

“We have some intel that they’re going to use some starters,” Schmetzer said.