Queens Park Rangers loanee Kevin Doyle has returned to parent club Wolverhampton Wanderers for treatment on a knee injury.
The 30-year-old striker's season looks over as he faces around six weeks on the sidelines after damaging ligaments during the win over Birmingham earlier this month.
Doyle was drafted in on transfer deadline day as cover for Rangers' top scorer Charlie Austin, who is still out with a shoulder injury, and scored two goals in six appearances.
Rangers manager Harry Redknapp said: "Kevin Doyle's long-term. He's gone back to Wolves.
"He's tweaked his knee ligaments so he's out for at least six weeks or so. It's a long job unfortunately."