The club remains top of the Premiership, but former Rangers midfielder Kevin Thomson believes the club missed a huge opportunity in the summer by keeping O’Neill as manager rather than moving him into a different role.

Speaking on The Breakdown alongside former Celtic defender Charlie Mulgrew, Thomson claimed Celtic should have appointed then-Motherwell boss Jens Berthel Askou and kept O’Neill around as a mentor or sounding board for the new manager.

Thomson said: “I do think, and it’s easy with hindsight, I did think how dramatic the last day of the season was, he should’ve just up sticks and left. But I still felt the club would be missing a trick.

“I think Martin would’ve been a brilliant foil, mentor or sounding board, somebody to speak to, somebody to confide in as part of whatever that looked like for Celtic, for the new manager coming in.

“Now he’s been the manager; he’s had it for a longer period of time rather than just short-term, you kind of feel as though Martin O’Neill wouldn’t work because he’s now attached himself to being the manager.”

O’Neill had led Celtic to the title last season after returning as manager, with the Hoops beating Hearts on the final day to seal the championship. He was already in the job on a permanent basis, while Askou left Motherwell to take charge of Toulouse.

Mulgrew believes Celtic could instead have installed Askou as manager and found a different position for O’Neill.

He said: “If he walks away then, Celtic still weighed him in with good money because he deserved that because of what he did with the title and then gave it to a Berthel Askou and let Martin O’Neill be director of football or be on the board or whatever.”

Thomson was even more emphatic about Celtic’s failure to move for Askou. He said: “It’s the biggest trick Celtic have ever missed, not getting him.”

Mulgrew added: “It’s a big one, isn’t it? I think he would have been desperate for it.

“He was always at Celtic Park.”

Thomson believes Askou could have been well suited to Celtic given the resources available at Parkhead and the style of football supporters have been accustomed to. He added: “You think of the resources that he would’ve had at his disposal and the type of players.

“He would be as close as getting a replacement that I think Celtic fans have been pining for since Ange Postecoglou.”