TORONTO - In the wake of their historic treble, Toronto FC's goalkeeper Alex Bono, fullback Justin Morrow and midfielder Marky Delgado have been called up by the U.S. national team.

Vancouver Whitecaps defender Tim Parker is also part of the 30-man roster for the annual U.S. January camp, which starts Wednesday in Carson, Calif. The Americans will play Bosnia and Herzegovina at the StubHub Center on Jan. 28 at the conclusion of the camp.

The American roster is made up of MLS players with the exception of former D.C. United 'keeper Bill Hamid, who is set to join Denmark's Midtjylland after the camp.

U.S. Soccer says acting head coach Dave Sarachan made the selections with a “focus on the future.” Toronto captain Michael Bradley and striker Jozy Altidore, who have 250 U.S. caps between them, were not called up.

Morrow, part of the U.S. Gold Cup team last summer, has three caps while Bono, Delgado and Parker are uncapped. Bono (2015) and Parker (2016) have attended the January camp before, however. And Delgado represented the U.S. at the U-20 World Cup in New Zealand, playing in all five matches.

Twenty-one of the 20 players invited to camp are 24 or younger.

Morrow, 30, had eight goals and one assist in 28 regular-season games in 2017 when he was a member of the MLS Best XI and a finalist for defender of the year.

Bono, 23, had a club-record 10 assists during a 19-4-6 regular season, taking over as the club's No. 1 'keeper.

Delgado, 22, had three goals and five assists in 26 matches.

Toronto won the MLS Cup, Canadian Championship and Supporters' Shield in 2017 while accumulating an MLS-record 69 points during the regular season.

Parker, 24, appeared in 32 regular-season games for the Whitecaps in 2017 with one goal and one assist.