Newcastle United boss Eddie Howe will not be in the St James’ Park dugout on Sunday when they play Manchester United in the Premier League.
The English manager has been hospitalised after feeling unwell for a number of days.
The Tyneside club said Howe is “conscious and talking with his family” but did not provide details of his illness.
A statement on their website read: “Medical staff kept Eddie in hospital overnight for further tests, which are ongoing.
“He is conscious and talking with his family, and is continuing to receive expert medical care.”
The club added: “Everyone at Newcastle United extends their best wishes to Eddie for a speedy recovery, and further updates will follow in due course.”
Howe’s absence means assistant managers Jason Tindall and Graeme Jones will lead the Magpies for Sunday’s clash at St James’ Park.
Newcastle have put together an impressive run of form recently, and are being regarded as favourites to win the upcoming game.
Losing their manager is a blow, but they are enjoying a four-match winning run in all competitions, with their latest success coming against Championship-bound Leicester City last weekend.
Howe’s men decided the fate of the contest inside the opening 35 minutes, as Jacob Murphy bagged a brilliant brace before Harvey Barnes netted a third from close-range.
Newcastle will be desperate to seal maximum points against United as they are aiming to qualify for next season’s Champions League.
On the other hand, the Red Devils’ priority is the Europa League as it offers the only route to secure European football next campaign.
With the quarter-final second leg against Lyon on Thursday, Ruben Amorim may decide to make changes against Newcastle on Sunday.