United States forward Bobby Wood missed Hamburg's Bundesliga defeat at promoted Hannover on Friday because of a reported knee injury.
Kicker magazine and local media reported that Wood, who had one goal from Hamburg's first three league games, has been bothered by a knee problem since the international break.
Wood, who scored late for the U.S. to salvage a 1-1 draw in a World Cup qualifier in Honduras on Sept. 6, played in Hamburg's 2-0 loss at home to Leipzig two days later but missed the side's subsequent training session.
Hamburg's long injury list -- forwards Nicolai Mueller, Filip Kostic and Aaron Hunt all have long-term injuries -- prompted the club to sign the previously club-less Bosnian veteran Sejad Salihovic on Wednesday.
Salihovic came on in the 60th minute on Friday night but Hamburg fell 2-0 to surprise Bundesliga leaders Hannover.