Manchester City striker Sergio Aguero has confirmed he has suffered a hamstring tear and is in Italy receiving treatment from a specialist.
The 24-year-old picked up the injury in the win over Stoke on New Year's Day and missed City's 3-0 FA Cup third-round victory over Watford.
Argentina international Aguero wrote on Twitter: "Studies confirmed I have a torn muscle.
"We have to keep thinking positive and try to recover in the best way."
It is not yet clear how long Aguero is likely to be out for.
City had hoped he would be fit to return against Arsenal on 13 January.
Aguero is City's joint top-scorer this season with 10 goals, level with Edin Dzeko.