Mauro Zarate has confirmed that he suffered a ruptured cruciate ligament during Watford's 1-1 draw with West Ham United on Saturday.
The January signing from Fiorentina was stretchered off after twisting his knee towards the end of the first half at Vicarage Road.
A scan on Sunday confirmed serious damage, and Zarate is now facing months of rehabilitation just three matches into his Watford career.
He wrote on Instagram: "Thank you everyone for your messages in this horrible moment.
"With sadness I inform you that the results show the following: anterior cruciate ligament rupture plus a Grade 1 injury of medial collateral ligament.
"I will face this with all my strength and will come back stronger than before."
Zarate has made a total of 12 appearances so far this season for Watford and Fiorentina.
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