No timeframe has been given for Eddie Howe's return to Newcastle but assistant Jason Tindall says the manager will be back as soon as he is "100% ready".
Howe was admitted to hospital with pneumonia on Friday, and missed his side's 4-1 win against Manchester United on Sunday.
He will also miss the next two games against Crystal Palace on Wednesday and Aston Villa on Saturday, with Tindall and coach Graeme Jones remaining in charge.
"We've had minimal dialogue together since that announcement," Tindall said.
"He's in the best possible hands and he'll be back as soon as he feels he's ready to come back 100% to lead the team.