Neil Lennon will take charge of Celtic until the end of the season after Brendan Rodgers agreed to take charge of Leicester, Press Association Sport understands.
The Parkhead club "very reluctantly" granted Rodgers permission to hold discussions with the Premier League outfit, who are looking for a successor to Claude Puel following his dismissal on Sunday.
And the Scottish champions moved quickly to install a replacement by lining up Lennon for a return to the job he left in 2014.
Lennon's appointment is expected to be confirmed later on Tuesday and he will attend a press conference at Celtic Park on Wednesday morning ahead of the Ladbrokes Premiership game against Hearts at Tynecastle later that evening.
— Celtic Football Club (@CelticFC) February 26, 2019
Lennon won three league titles and two Scottish Cups in just over four years as Celtic manager after taking over from Tony Mowbray, initially on a temporary basis, in March 2010.
Rodgers' departure has proven to be a swift farewell after Celtic confirmed Leicester's approach early on Tuesday.
A Celtic statement read: "Celtic Football Club today confirmed that it has been approached by Leicester City FC to speak to Brendan Rodgers with regards to their current managerial vacancy.
"Brendan has indicated to the club that this is an opportunity he wishes to investigate further and therefore, very reluctantly, the club has granted him permission to speak to Leicester City."
Dream job and to leave now... it stinks⚽️ https://t.co/iE2nTyURPu
— Chris Sutton (@chris_sutton73) February 26, 2019
Former Celtic striker Chris Sutton criticised Rodgers over the timing of his expected departure.
Sutton told BT Sport's Twitter account: "The timing of it stinks. He's going to a club who are playing for absolutely nothing – they are not going to get relegated, they are not going to get into Europe – and I am really disappointed.
"I think there are a lot of Celtic fans out there as well who will feel let down.
"This is the job which Brendan said was his dream job. So why is he going now to a club who have nothing to play for?"