David Wagner's sweating on the fitness of Aaron Mooy ahead of Huddersfield Town's visit to St James's Park.
Mooy wasn't involved in Australia's goalless draw against Colombia at Craven Cottage last night after suffering a "minor injury setback".
The winger is now being assessed by Huddersfield ahead of Saturday's game against Newcastle United.
Mooy had a spell out last month with an infection in a knee he cut against Bournemouth.
The 27-year-old is a key player for Huddersfield manager Wagner, whose side is 15th in the Premier League table and a point behind 13th-placed Newcastle.
Mooy's midfield colleague Philip Billing returned home early from international duty with Denmark's Under-21s after suffering an injury.
Meanwhile, United are "assessing" winger Matt Ritchie after the winger withdrew from the Scotland squad with an unspecified injury.