The Uruguay international had slowly been regaining match fitness in the wake of February's ACL injury, and he made his first start since that fateful day against Aston Villa last weekend.
However, Bentancur's afternoon was cut short in the first half of that 2-1 defeat, as he was the victim of a reckless challenge from Matty Cash and trudged off the field to be replaced by Pierre-Emile Hojbjerg in the 32nd minute.
Reports earlier this week claimed that the luckless Bentancur would be unavailable for around 10 weeks, and Postecoglou confirmed the worst to Spurs' media channels ahead of Sunday's clash with champions Manchester City at the Etihad.
«It's disappointing for him, the outcome wasn't great so he'll probably miss a fair chunk of time between now and the New Year, probably a couple of months for him to get back,» Postecoglou told Spurs' social media channels.
«We all know how hard he's worked to get himself back and playing for his country, it was his first start and he started awfully well for us. For him, everyone's feeling gutted but he's such a positive guy. He can't wait to get cracking again and I've got no doubt we'll see him back as soon as possible.»
No sooner had Bentancur exited the treatment room before re-entering the packed infirmary, which also holds James Maddison (ankle), Micky van de Ven (thigh), Ryan Sessegnon (hamstring), Ashley Phillips (ankle), Ivan Perisic (knee), Manor Solomon (knee) and Alfie Whiteman (ankle).
Richarlison is also working his way back from a groin operation, while Pape Sarr sat out the loss to Aston Villa with an
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