SAO PAULO — Jozy Altidore will miss the Americans' World Cup game against Portugal on Sunday because of his strained left hamstring and appears likely to sit out next week's match against Germany.
The U.S. probably needs to advance to the knockout phase if the forward is to return to the tournament.
Altidore was hurt in the 21st minute of Monday's 2-1 win over Ghana, and the U.S. Soccer Federation said Thursday he will not play against the Portuguese.
"He's a big player for us," midfielder Kyle Beckerman said. "We're extremely bummed for him and for the team, but we bring 23 players, and it's just a chance for somebody to step up. Hopefully the injury's not too bad and we can see Jozy later in the tournament."
U.S. team spokesman Michael Kammarman did not reveal the severity of the strain. The Americans have just three days off between this weekend's game in Manaus and their first-round finale in Recife on June 26.
"It's bad news, but I think the team will handle this," midfielder Jermaine Jones said. "We have to handle that."
Aron Johannsson replaced Altidore for the second half against Ghana. Chris Wondolowski is the other striker who could join Clint Dempsey in the attack.
A 31-year-old Californian, Wondolowski led Major League Soccer with 18 regular-season goals in 2010 and 27 in 2012, and tied for the lead with 16 in 2011.
"He can score from anything, score when you think there's nothing, no chance, and next thing you know he scores," Beckerman said. "He works his tail off for the guy behind him. He does a lot of things that don't show up on the stat sheet."
Johannsson, a 23-year-old who was born in Mobile, Alabama, and grew up in Iceland, scored 26 goals last season for AZ Alkmaar in the Netherlands.
"Wondo is more the finisher in the box," Jones said. "Aron is more maybe the guy who's good with the ball and tries to go one against one."
Coach Jurgen Klinsmann also could opt to shift from the 4-4-2 formation he used in the opener and start five midfielders.
Dempsey has not decided whether he will wear a mask to protect his nose, which was broken during the Ghana game by John Boye's shin to his face during a battle for a header.
Defender Matt Besler, who left the Ghana match at halftime because of a sore right hamstring, should be available for Sunday's game, Kammarman said.
Portugal also has issues after its opening 4-0 loss to Germany. Central defender Pepe was ejected after he appeared to head butt Thomas Mueller, right back Fabio Coentrao was taken off on a stretcher and forward Hugo Almeida limped off. Pepe is suspended for Sunday's game, and Coentrao is out for the tournament.