Liverpool have suffered a double injury blow with midfielders Thiago Alcantara and Naby Keita both ruled out for their clash with Brentford.
Jurgen Klopp's side travel to London hoping to keep up an unbeaten start to the Premier League season that sees them level on points with Chelsea and Manchester United at the top of the table.
Klopp revealed that Thiago is expected to be out beyond the next international break, while Keita is also a doubt for Tuesday 28 September's Champions League trip to Porto.
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"It's not 100 per cent clear when Thiago will be back," Klopp explained ahead of his side's visit to the Brentford Community Stadium.
It's a muscle in the calf issue, so after the international break, probably.
"I don't think there's anything earlier possible - we will have to see."
Keita suffered his injury during the first half of midweek Carabao Cup action against Norwich after kicking the turf.
The Guinean failed to re-emerge after the half-time interval.
His manager stressed that while the injury was not major, Keita may also miss a tricky visit to Portugal.
Klopp said: "[It’s] nothing really serious, but it keeps him out of the next game for sure – and maybe a little bit longer, we have to see.

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It’s obviously painful and we have to see how we can deal with it. Of course, it’s not cool when players have had a good pre-season, could play a lot of games and now are out.
"That happens throughout a season and hopefully when they come back then that’s it and they can play the rest of the season, that would be extremely helpful.”
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