Prop Scott Anderson will not play for Wakefield for "at least" two months after suffering a knee injury in their 58-16 defeat by Widnes last weekend.
The 29-year-old played 20 Super League matches last season after joining from National Rugby League side Brisbane, and started all three games this term.
"It's medial knee ligament and maybe cartilage damage as well," head coach James Webster told BBC Radio Leeds.
"It's at least eight, but could be 12 weeks. We're waiting for scan results."
Webster added: "If I'm honest I doubt we'll get anyone in on loan. With all the fixtures over Easter, teams want to keep hold of their players."