The Town striker has been sidelined of late with a thigh injury which manager Lee Clark has rvealed is worse than first feared.
"Robbie's recovery from a thigh injury has been slower than we first thought," Clark has told the club's official website.
"As a result he has had a scan at the hospital, which revealed a second degree tear. This means he could be out for up to a month.
"That's not just a blow for us, but it's bitterly disappointing for Robbie.
"He's had a really stop-start beginning to his Huddersfield Town career."