AFC Wimbledon defender Callum Kennedy has suffered a setback in his recovery from an ankle injury.
The 24-year-old former Swindon full-back has been sidelined since damaging a tendon during the 2-1 win over Exeter City back in January.
Dons physio Stuart Douglas told the club website: "Callum has seen a specialist, and ultrasound scans show that the fluid-filled sheath that surrounds the tendon is inflamed.
"This condition can be very difficult to treat and I cannot yet estimate when he will return to fitness."
The Dons have also confirmed that long-term injury absentees Charlie Strutton and Rhys Weston will miss the rest of the season.