Fabian Johnson played 78 minutes against Hannover on Saturday. (Sacha Steinbach/EPA-EFE, REX/Shutterstock)

Bruce Arena made five changes to the U.S. national soccer team ahead of the last two World Cup qualifiers, with Fabian Johnson’s exclusion and Benny Feilhaber’s inclusion as the biggest surprises.

A day after playing 78 minutes in Moenchengladbach’s 2-1 Bundesliga victory over Hannover, Johnson was not among 26 players summoned to U.S. training camp in Orlando.

Fitness issues — and concerns about how the veteran wing would perform in hot conditions in Florida and the Caribbean — were apparently at the root of Arena’s decision. Johnson also started last weekend against Borussia Dortmund but has logged just 180 minutes in four club appearances (two starts) since the German league commenced six weeks ago.

Still, his omission before two vital matches came as a shock. Johnson was a standout at the 2014 World Cup, started each of the past two home qualifiers and offers flexibility to serve in midfield or defense. In comments distributed by the U.S. Soccer Federation, Arena did not address Johnson.

One other regular was left behind: Seattle Sounders forward Jordan Morris (hamstring injury).

The Americans (2-3-3, nine points) sit fourth in the six-nation CONCACAF race and are probably going to need to defeat third-place Panama (2-2-4, 10) on Friday at Orlando City Stadium and beat or draw bottom-dwelling Trinidad and Tobago (1-7-0, three) on Oct. 10 in Port of Spain in order to clinch one of three automatic berths in next summer’s World Cup in Russia. A fourth team will advance to an intercontinental playoff next month against Australia or Syria.

“If it comes down to where we need four or six points in our last two games,” Arena said, “I think that’s fine and we’ll get it done.”

Three reserves from the September matches were also passed over: Seattle midfielder Cristian Roldan, FC Dallas defender Matt Hedges and Nottingham Forest defender Eric Lichaj, who has played just 13 minutes in England’s second tier this season.

Johnson’s roster slot went to Gyasi Zardes, a Los Angeles Galaxy attacker and defender who was a member of Arena’s Gold Cup championship team this summer. Zardes, however, suffered a groin strain in the Galaxy’s match late Saturday and withdraw from the U.S. roster Sunday. No replacement was named, leaving 25 players for the start of camp Monday.

Lichaj was expendable because Newcastle’s DeAndre Yedlin, Arena’s first-choice right back, is at full health after missing two U.S. matches in September with a hamstring injury. Sporting Kansas City’s Graham Zusi started on the right side in the past two qualifiers and could end up in the lineup against Trinidad and Tobago.

Yedlin wasn’t the only English-based defender to recover from injury. Stoke City’s Geoff Cameron, who played in both September qualifiers, seemed unlikely to rejoin the U.S. team after pulling a muscle three weeks ago. On Saturday, though, he started against Southampton.

New England Revolution forward Juan Agudelo, a Gold Cup member, will take Morris’s place on the roster, while Michael Orozco, with Mexican club Tijuana, replaced Hedges.

Feilhaber, a 32-year-old attacking midfielder for Sporting Kansas City, last appeared in U.S. camp in the winter, Arena’s first get-together after taking the job. He performed well in two friendlies but didn’t receive a callback until this weekend, ostensibly replacing Roldan, 22, who made his international debut this summer.

Only 23 players are permitted to be in uniform for international matches, but with nine in danger of being suspended for the last qualifier, Arena assembled a larger group. Cameron, Yedlin, Michael Bradley, Clint Dempsey, Matt Besler, Kellyn Acosta, Paul Arriola, DaMarcus Beasley and Alejandro Bedoya are carrying yellow cards and, with a caution against Panama, would miss the Trinidad and Tobago match.

“If any issues arise,” Arena said, “we have cover in all positions.”

U.S. ROSTER

Goalkeepers: Brad Guzan (Atlanta United), Tim Howard (Colorado Rapids), Nick Rimando (Real Salt Lake).

Defenders: DaMarcus Beasley (Houston Dynamo), Matt Besler (Sporting Kansas City), Geoff Cameron (Stoke City), Omar Gonzalez (Pachuca), Michael Orozco (Tijuana), Tim Ream (Fulham), Jorge Villafaña (Santos Laguna), DeAndre Yedlin (Newcastle United), Graham Zusi (Sporting Kansas City).

Midfielders: Kellyn Acosta (FC Dallas), Juan Agudelo (New England Revolution), Paul Arriola (D.C. United), Alejandro Bedoya (Philadelphia Union), Michael Bradley (Toronto FC), Benny Feilhaber (Sporting Kansas City), Dax McCarty (Chicago Fire), Darlington Nagbe (Portland Timbers), Christian Pulisic (Borussia Dortmund).

Forwards: Jozy Altidore (Toronto FC), Clint Dempsey (Seattle Sounders), Chris Wondolowski (San Jose Earthquakes), Bobby Wood (Hamburg).