By Michael Kahn
NATAL, Brazil, June 19 (Reuters) - Hampered by a depleted strike force, the United States are likely to choose between a young Icelandic import or a veteran super-sub to lead the line in place of the injured Jozy Altidore for their World Cup match against Portugal.
U.S. coach Juergen Klinsmann lacks someone in the squad able to muscle past defenders and create space and opportunities for others like the burly Altidore, whose hamstring injury has probably ruled him out of the rest of the tournament.
After dispatching Ghana 2-1 in a dramatic Group G opener, the United States know victory against the Portuguese on Sunday should put them through to the last 16 for the fourth time in the last seven tournaments.
But without the striker who has long been a key cog in the U.S. attack, the Americans are left with two untested players to partner captain Clint Dempsey, who is nursing a broken nose and may be forced to play with a protective mask.
"It wasn't easy to swallow the first pill with Jozy coming off the field," Klinsmann said after the Ghana match. "He is very, very important to us."
Altidore's injury and the paucity of proven replacements have also revived questions over Klinsmann's decision to leave Landon Donovan and other experienced players at home.
Aside from leaving all-time national team scoring leader Donovan out of the squad, Klinsmann omitted Terrence Boyd, a mobile, physical player who can play as a target man and would have been more of a straight swap for Altidore.
Klinsmann is now likely to choose between Aron Johannsson, who made little impact when he came on against Ghana, and Chris Wondolowski, a 31-year-old Major League Soccer veteran.
Johannsson, whose was born in Alabama but grew up in Iceland, gave the U.S. team a pacy striker when he pledged his football future to the United States last year.
The 23-year-old, known as "iceman" for his cool finishing, was one of the top scorers in the Dutch top flight last season, knocking in 17 league goals for AZ Alkmaar.
Although a proven goal-scorer at club level, Johannsson has made nine appearances for the United States and against Ghana had trouble making much of an impact against a quick, physical defence.
Wondolowski is a hard-working striker who has spent his entire professional career in Major League Soccer and is untested at the highest levels in club football.
More of a poacher than a true target man, Wondolowski is a former MLS scoring leader but his nine goals for the national team have come mainly in friendlies or against weak opponents.
Klinsmann has expressed confidence in his entire squad but whoever gets handed the job has his work cut out for him in the jungle heat of Manaus even against a Portugal defence missing Fabio Coentrao and Pepe due to injury and suspension. (Reporting by Michael Kahn, Editing by Ed Osmond)