With key World Cup qualifiers coming up, coach Bruce Arena has called in a mixture of veterans and young players for the U.S. team's training camp in Denver.

"I think we have a good group," Arena said Sunday. "I'm still in the early goings with this team and I haven't seen all of our players, so this camp gives me the opportunity to see six new faces we haven't had in with the team yet, which is valuable. It's also great that we're able to bring back 21 players that have been in with our program already in 2017."

Those new faces to Arena, who returned to national team duty last year when Jurgen Klinsmann was fired, are goalkeepers Brad Guzan and Ethan Horvath, defenders Timmy Chandler, DeAndre Yedlin and Fabian Johnson, and forward Bobby Wood. All except Guzan play for clubs in Europe, though Guzan saw some time last season with Middlesbrough in England.

Missing from the 27-man roster is Los Angeles Galaxy midfielder Jermaine Jones, often a regular in international games. Jones, bothered by a sprained right knee, might not fit Arena's plans as Michael Bradley is used in more of a defensive midfield role that Jones has filled.

Tim Howard, Guzan and Nick Rimando, fixtures guarding the net, were chosen along with 21-year-old Horvath of Club Brugge in Belgium.

"I think we're going to camp with three good, experienced goalkeepers," Arena said. "In Ethan Horvath's case, he's one of our young, promising goalkeepers that we need to see. We won't have the opportunity to see him for the Gold Cup (this summer), so we wanted to see him in this camp, and he's also from Denver, so it worked out pretty well."

After the Americans play a tuneup against Venezuela in Sandy, Utah, on Saturday, they have the qualifiers against Trinidad and Tobago on June 8 in Commerce City, Colorado, and then at archrival Mexico three days later. The United States is fourth in the six-team hextagonal after a rough start under Klinsmann. The Americans routed Honduras 6-0 and tied Panama 1-1 under Arena.

Other mainstays called in by Arena included Bradley, Alejandro Bedoya and Dax McCarthy in midfield; Clint Dempsey and Jozy Altidore at forward; and defenders DaMarcus Beasley, Geoff Cameron, Johnson and Chandler.

Defender Matt Hedges of FC Dallas was invited to his first camp ahead of a qualifier. Hedges was injured earlier this year and missed friendlies against Serbia and Jamaica.

"We can't ignore the fact that Matt's been a good player and he needs an opportunity with the national team," Arena said. "Bringing him in is a plus, it'll get him a foot in the door and hopefully allow him to move forward with a bigger role in the U.S. team."

On the other end of the experience spectrum is Beasley, an Arena favourite who has 124 caps. At 35, Beasley is the oldest field player on the roster.

"I think he's had a great career and the longevity speaks for itself," Arena said. "He's still been a good player in Major League Soccer, and that's why we still have him on the roster. We haven't found any players that can push DaMarcus out of the position he has right now with the national team.

"He's not only a good player, he's a good teammate, and he's going to do whatever is necessary to make our team successful."

The top three teams in the CONCACAF final round qualify for next year's World Cup in Russia. The fourth-place nation will play off against a team from Asia for another berth.

The roster:

GOALKEEPERS: Brad Guzan (Atlanta United FC), Ethan Horvath (Club Brugge, Belgium), Tim Howard (Colorado Rapids), Nick Rimando (Real Salt Lake)

DEFENDERS: DaMarcus Beasley (Houston Dynamo), Matt Besler (Sporting Kansas City), John Brooks (Hertha Berlin, Germany), Geoff Cameron (Stoke City, England), Timmy Chandler (Eintracht Frankfurt, Germany), Omar Gonzalez (Pachuca, Mexico), Matt Hedges (FC Dallas), Tim Ream (Fulham, England), Jorge Villafana (Santos Laguna, Mexico), DeAndre Yedlin (Newcastle United, England), Graham Zusi (Sporting Kansas City)

MIDFIELDERS: Kellyn Acosta (FC Dallas), Paul Arriola (Club Tijuana, Mexico), Alejandro Bedoya (Philadelphia Union), Michael Bradley (Toronto FC), Fabian Johnson (Borussia Moenchengladbach, Germany), Dax McCarty (Chicago Fire), Darlington Nagbe (Portland Timbers), Christian Pulisic (Borussia Dortmund, Germany)

FORWARDS: Jozy Altidore (Toronto FC), Clint Dempsey (Seattle Sounders FC), Jordan Morris (Seattle Sounders FC), Bobby Wood (Hamburg SV, Germany)