Scott Sinclair's stinging criticism of Roberto Mancini in 2013

Head coach of FC Zenit Roberto Mancini during the Russian Premier League match between FC Rubin Kazan and FC Zenit Saint Petersburg at Kazan Arena stadium on November 5, 2017 in Kazan,...

The Celtic winger will have a point to prove against Zenit St Petersburg this week.

Head coach Roberto Mancini of FC Zenit Saint Petersburg gestures during the Russian Premier League match between FC Spartak Moscow and FC Zenit Saint Petersburg at Otkrytie Arena stadium...Head coach Roberto Mancini of FC Zenit Saint Petersburg

Celtic take on Zenit St Petersburg in the UEFA Europa League this week, looking to disprove the critics who feel the Scottish side will find themselves out of their depth against the Russian outfit.

One player who will have something to prove in the game is winger Scott Sinclair. The Celtic forward, who was one of the star players for Brendan Rodgers last season, played under Zenit boss Mancini during his time at Manchester City.

That was a poor career move from Sinclair, who went on to struggle for first-team football at City effectively wasting three years of his career.

Morgaro Gomis of Heart of Midlothian tackes Scott Sinclair of Manchester City during the pre-season friendly at Tynecastle Stadium on July 18, 2014 in Edinburgh, Scotland.Morgaro Gomis of Heart of Midlothian tackes Scott Sinclair of Manchester City 

This week he has spoken about his time at City and warned Mancini he is a better player now than he was during his time at City.

The pair were never really had a good relationship. When Sinclair left City for West Brom on loan in 2015 he had this to say about Mancini. He was quoted by the Independent as stating:

"I even asked him 'Why did you bring me in if you're not going to give me a chance? You've given me no game time to show what I'm about', and he couldn't really answer the question.

"As a player, if you're not getting a chance to play then you are going to see the manager and ask him what is needed.

"So I did see him a few times, and we had our differences, but that's football.

"Not being given an opportunity to play was frustrating, but that was the choice I made, I never kicked up a fuss. All I could do was put my head down and train every day."

Scott Sinclair of Celtic vies with Daniel Candeias of Rangersduring the Scottish Premier League match between Celtic and Ranger at Celtic Park on December 30, 2017 in Glasgow, Scotland.Scott Sinclair of Celtic vies with Daniel Candeias of Rangers

When Mancini signed the player it was rumoured to have been a decision perhaps based on the club’s need to improve on homegrown talents in the squad after new UEFA regulations.

The fact is, Sinclair never got a chance under Mancini at the Etihad and his career stalled as a consequence.

Now he is back on form at Celtic and will be looking to get the better of his old boss over two legs in the Europa League.

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