There are few cases more curious in Scottish football than that of Olivier Ntcham.
When at his best for Celtic the French midfielder had a genuine claim to being the pre-eminent midfielder in Scotland, able to control a game almost on his own.
One of the high water marks of the Brendan Rodgers era was a 5-0 demolition of Rangers at Parkhead in April 2018 and Ntcham was the chief tormentor of the Ibrox side.