U.S. national team coach Juergen Klinsmann exercised the option of replacing up to four players for the CONCACAF Gold Cup knockout stages with three predictable selections and one surprise.

Defenders Omar Gonzalez and Matt Besler and forwards Eddie Johnson and Alan Gordon are in.

Defenders Oguchi Onyewu and Corey Ashe and forwards Herculez Gomez and Jack McInerney are out.

CONCACAF announced the changes tonight. The U.S. Soccer Federation confirmed their accuracy to the Insider.

The new quartet will join the U.S. squad in Baltimore ahead of Sunday’s 4 p.m. quarterfinal against El Salvador at M&T Bank Stadium (Fox’s main channel, Univision).

Gonzalez (Los Angeles Galaxy) and Besler (Sporting Kansas City) were Klinsmann’s first-choice partnership in central defense during last month’s World Cup qualifiers. He did not initially call them for the Gold Cup, allowing them instead to remain with their in-season MLS clubs. They were among a dozen players on stand-by for the later rounds.

Johnson (Seattle Sounders) was another regular during the qualifying campaign and was allowed to skip the first portion of Gold Cup duty to play in MLS matches. Gordon (San Jose Earthquakes) has participated in U.S. camps but has not figured in the qualifiers this year.

In the Gold Cup group stage, Gomez started once and entered as a substitute once. Onyewu, back in the U.S. mix for the first time since last summer, started once. Ashe (thigh injury) and McInerney, in his first senior national team call-up, did not play.

Gomez, whose Mexican season with new club Tijuana starts Friday, and Onyewu (Sporting Lisbon) are free to report to respective training camps. Ashe (Houston Dynamo) and McInerney (Philadelphia Union) will rejoin their MLS teams for weekend matches.

The most curious omission in today’s call-ups: Graham Zusi, who started on the right side of midfield in the qualifiers. Klinsmann must be pleased with his flank play and attack in general in allowing Zusi to remain with Sporting KC. Bolstered by the return of Landon Donovan, the rise of forward Chris Wondolowski (five goals) and a light schedule (Belize, Cuba and Costa Rica), the Americans scored 11 times in group play.

They will resume workouts Friday morning in the Baltimore area.

Four of the eight quarterfinalists did not make any roster changes. The complete list is here.

Promoters say more than 43,000 tickets have been sold for Sunday’s quarterfinal doubleheader: USA vs. El Salvador, followed by Honduras vs. Costa Rica.