Eddie Howe will miss Sunday's Premier League game against Manchester United after being admitted to hospital.
Howe was admitted to the hospital late on Friday "having felt unwell for a number of days," Newcastle said in a statement.
A club statement continued: "The Magpies' head coach was admitted to hospital late on Friday evening having felt unwell for a number of days.
"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.
"Everyone at Newcastle United extends their best wishes to Eddie for a speedy recovery, and further updates will follow in due course."
Howe's assistants, Jason Tindall and Graeme Jones will lead the team for the game at St. James' Park, which kicks off at 4.30pm, live on Sky Sports.
Tindall stood in for Howe at the club's pre-match press conference.
Howe guided Newcastle to their first domestic trophy for 70 years last month with a Carabao Cup final win over Liverpool at Wembley.
He has been in charge on Tyneside since November 2021, when he succeeded Steve Bruce.
Newcastle are currently seventh in the Premier League table and bidding to secure Champions League qualification after their cup success.
