USA head coach Gregg Berhalter has called in 25 MLS based players into a national team training camp ahead of a friendly with Slovenia, the start of preparations for June's Copa America.

With the January 20 game in San Antonio falling outside of the FIFA international window, Berhalter is not able to call on his usual squad of mainly Europe-based players.

But Berhalter plans to take a closer look at young MLS players who might yet have hopes of forcing their way into his squad in time for the Cope America.

The USA will face Uruguay, Panama and Bolivia in group C of the 16-team tournament which is being hosted in the States.

There are also 13 players in the squad who are eligible for July's Paris Olympic football tournament and under-23 coach Marko Mitrovic will be part of Berhalter's staff at the camp.

"This is an opportunity to identify and work with the next generation of players who have the potential to make an impact on our program," Berhalter said.

"We appreciate the support from MLS and all their clubs so that we can utilize this platform. Our priority is on getting as many players as possible experience in important competitions, and this camp and the match against Slovenia will be extremely valuable in the evaluation process," he said.

The squad includes 17 uncapped players among them goalkeeper Patrick Schulte who impressed with Columbus Crew during their run to the MLS title last season.

Another Crew player, with a more realistic chance of making the Copa America squad, is midfielder Aidan Morris while attacking midfielder Diego Luna of Real Salt Lake will also have a chance to impress Berhalter.

Defender Miles Robinson, who moved this week from Atlanta United to FC Cincinnati, is the most capped player in the roster with 27 appearances.

The team will train in Orlando from January 8 to 16 before heading to Texas ahead of the Slovenia game.

In March, the USA will compete in the Final Four of the CONCACAF Nations League in Arlington, Texas when they face Jamaica in the semi-final before taking on Panama or Mexico in the March 24 final at AT&T Stadium, the home of the NFL's Dallas Cowboys.

Squad:

Goalkeepers: Drake Callender (Inter Miami), Roman Celentano (FC Cincinnati), Patrick Schulte (Columbus Crew)

Defenders: Nathan Harriel (Philadelphia Union), DeJuan Jones (New England Revolution), Shaq Moore (Nashville SC), Ian Murphy (FC Cincinnati), Jackson Ragen (Seattle Sounders), Miles Robinson (FC Cincinnati), James Sands (New York City FC), Nkosi Tafari (FC Dallas), John Tolkin (New York Red Bulls), Caleb Wiley (Atlanta United)

Midfielders: Joshua Atencio (Seattle Sounders), Aziel Jackson (St. Louis City), Jack McGlynn (Philadelphia Union), Aidan Morris (Columbus Crew), Timmy Tillman (LAFC), Sean Zawadzki (Columbus Crew)

Forwards: Esmir Bajraktarevic (New England Revolution), Cade Cowell (San Jose Earthquakes), Bernard Kamungo (FC Dallas), Diego Luna (Real Salt Lake), Duncan McGuire (Orlando City), Brian White (Vancouver Whitecaps/CAN)