UPDATE, July 25:

Defenders Per Mertesacker and Gabriel were not included in the squad that traveled to the USA. Mertesacker has a knee injury, the club said, and Gabriel has tonsillitis.

And here's who you can expect to see at #ArsenalUSA! pic.twitter.com/5rQeQOoh0s — Arsenal FC (@Arsenal) July 25, 2016

You may have spotted one notable absentee - @mertesacker has a knee problem and won’t be part of #ArsenalUSA pic.twitter.com/GwEWg0T4Dw — Arsenal FC (@Arsenal) July 25, 2016

ORIGINAL TEXT, July 23:

The 2016 AT&T MLS All-Star Game always figured to be a challenging game for the league's best players, but now we have a clearer idea as to just how tough it might be.

Arsenal announced their 25-man preliminary roster for the upcoming meeting with the MLS All-Stars, and it includes heavy hitters like Alex Oxlade-Chamberlain, David Ospina, and Per Mertesacker. Other notable players that manager Arsene Wenger named to the squad are Petr Cech, Theo Walcott, Jack Wilshere, Joel Campbell, and US youth national team member Gedion Zelalem.

The Gunners, who are also facing Mexican outfit Chivas Guadalajara during their Stateside trip, did not include first-team players like Alexis Sanchez and Mesut Ozil, both of whom went deep in international competition this summer, on the preliminary list.

“The players who won’t make it are the players who went very far in the European Championship, such as [Aaron] Ramsey, Ozil, [Olivier] Giroud and [Lauren] Koscielny,” Wenger told Arsenal.com news editor Rob Kelly. “I left Gabriel behind today because he has tonsillitis and is infected. He cannot travel. [And] Alexis will not go either because he had an ankle injury, and I will leave him behind as well.”

The roster remains subject to change.

Arsenal will play the MLS All-Stars at Avaya Stadium in San Jose, California, on July 28 (7:30 pm ET | ESPN, UniMás, TSN and RDS).

Here is Arsenal's complete preliminary roster for the 2016 MLS All-Star Game:

Goalkeepers (3): Petr Cech, David Ospina, Emiliano Martinez

Defenders (9): Hector Bellerin, Krystian Bielik, Calum Chambers, Mathieu Debuchy, Gabriel*, Kieran Gibbs, Rob Holding, Per Mertesacker, Nacho Monreal

Midfielders (9): Santi Cazorla, Francis Coquelin, Mohamed Elneny, Alex Oxlade-Chamberlain, Jeff Reine-Adelaide, Chris Willock, Jack Wilshere, Granit Xhaka, Gedion Zelalem

Forwards (4): Chuba Akpom, Joel Campbell, Alex Iwobi, Theo Walcott

*As noted in the text, Wenger has said Gabriel will not travel due to tonsillitis.