Celtic striker Mohamed Bangura has suffered a setback in his recovery from the latest episode of knee trouble to have interrupted his Parkhead career.
The Sierra Leone international was expected to be out for only a short spell after it emerged at the start of January he had suffered another injury, having already missed a chunk of the season.
But Celtic reported on Wednesday that the 22-year-old, who has yet to score since his summer move from Swedish side AIK, is not recovering as well as was hoped.
According to the club's official website, Bangura has "tweaked" his right knee once more, with a specialist due to assess the injury next week.
Celtic also announced that defender Daniel Majstorovic is available for selection ahead of this weekend's Scottish Communities League Cup semi-final against Falkirk at Hampden, having returned to training following the fractured cheekbone he suffered against St Johnstone last month.
Manager Neil Lennon's options will also be increased ahead of the weekend when new-recruit defender Mikael Lustig and winger Paddy McCourt return to training after their respective thigh and foot injuries.