The midfielder has been a regular fixture in the Arsenal team this season and he has been one of the first names on Wenger’s team sheet for most of the campaign.
However, the Switzerland international has been struggling with the flu in recent days and he was left back in London as his team-mates took on CSKA in the quarter-final second leg in Russia.
Speaking at his pre-match news conference before the game on Wednesday night, Wenger said: “Xhaka is not here with flu.”
Xhaka has scored one goal and made five assists in 32 Premier League appearances for Arsenal so far this season.
It remains to be seen whether Xhaka will have recovered in time to be fit for Arsenal’s Premier League clash against Newcastle United at St James’ Park on Sunday afternoon.
The north London side are aiming to finish as highly as possible in the Premier League table this season, although their hopes of securing a top-four finish are looking very slim.
Arsenal are currently in sixth place in the Premier League table after having ended up in fifth place in the table last term.
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