"All good. He's back home and he's fine. He is feeling good," Postecoglou said.
"Thankfully, it looks like a concussion and nothing more than it."
"Obviously, you follow the protocols now and it's a couple of weeks where you have to make sure everything is okay."
Spurs travel to National League side Tamworth in the third round of the FA Cup on Sunday (12.30pm GMT).
It is the first of four matches Bentancur will miss under the 14-day protocol period.
Tottenham travel to rivals Arsenal on 15 January and relegation-threatened Everton on 19 January in the Premier League, before a trip to Hoffenheim in the Europa League on 23 January.