Omar Gonzalez promised from Day 1 of training camp to be ready for the World Cup, even if he started slightly behind because of a knee injury.

U.S. coach Jurgen Klinsmann took a chance on the L.A. Galaxy star for Thursday's Group G finale against three-time champion Germany, inserting Gonzalez for struggling right center back Geoff Cameron in the 1-0 loss that was still enough for the U.S. to advance in Brazil. Portugal defeated Ghana 2-1 at nearly the same time.

Aside from an early missed clearance attempt by Gonzalez in the third minute when he flubbed Jerome Boateng's cross and nearly put it in his own net, the move paid off for Klinsmann and the Americans.

They have defied expectations by getting out of one of this tournament's toughest groups. The U.S. is headed to the knockout round in consecutive World Cups for the first time.

A top defender in Major League Soccer, Gonzalez hung tough against high-scoring Germany on a soggy field and with a slippery ball.

Gonzalez hurt his left knee May 3 against Colorado, keeping him out for the start of Klinsmann's structured training camp last month at Stanford, California.

He hoped it wouldn't put him behind. Clearly, Klinsmann trusted Gonzalez to take over a big responsibility on a new-look back line that has been scrutinized from the start for its youth and inexperience on soccer's biggest stage.

Against second-ranked Germany, Gonzalez didn't flinch. His 6-foot-5, 210-pound frame certainly helped him to win possession on headers.

He received a quick, congratulatory pat on the backside from goalkeeper Tim Howard when he cleared a ball in the 14th minute, then a high-five from fellow center back Matt Besler after another hard tackle against Thomas Mueller.

Gonzalez, who joined the national team player pool in 2009, cleared another potential chance for Germany after the ball deflected off Howard in front of the box.

The 25-year-old defender from Dallas made his World Cup debut in the 91st minute of Sunday night's 2-2 draw with Portugal in Manaus, then made an even bigger impact in his first start with his team's World Cup hopes on the line and chants of "U-S-A!" ringing through Arena Pernambuco.

While the Americans didn't exactly get their ideal result, the defense didn't allow the Germans a game like their 4-0 romp over Portugal in the opener.

When the final whistle blew and the Americans quickly learned of Portugal's win, No. 3 goalkeeper Nick Rimando sprinted out and leapt into Gonzalez's arms.

Gonzalez joined his teammates for a walk around the stadium, then stopped and gave a two thumbs-up salute, a wave and a clap before making his exit.