The Brazil international was tearful as he admitted his ``dream'' of playing in Qatar was now in serious jeopardy.
The forward was forced off in the 52nd minute of Tottenham's 2-0 win in the Premier League and was later seen on crutches.
``It's kind of hard to say because it's close to the realization of my dream,'' Richarlison told ESPN Brazil. ``I've already suffered a similar injury to this but I hope it can heal as soon as possible.
``The last time when I was at Everton, I was out of action for about two months.``
Richarlison was expected to be part of Brazil head coach Tite's squad for the World Cup, which will be named at the beginning of November.
``For sure against Manchester United he's out (on Wednesday),'' Tottenham manager Antonio Conte said. ``I think he needs a bit of time to recover. It's a pity because we are talking about a player who gives us a lot of quality, but is also strong and improves our intensity.``
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