When Celtic confirmed the £2.25m signing of Teemu Pukki back in the summer of 2013, expectations for the then-23-year-old centre-forward were extremely high at Parkhead.

Indeed, the young striker had been impressing with FC Schalke 04, scoring eight goals and registering three assists over his 47 appearances for the 2. Bundesliga side, while Neil Lennon also appeared to be incredibly excited by the Finland international's potential.

Following his arrival in Glasgow, the Celtic manager said: "He's a player we've liked for quite a while. We like his style of play, I think he'll suit us. His first touch is excellent. He's a similar size to Gary [Hooper]. He may not bring the weight of goals Gary did but I know for a fact he'll make us a better team.

"I watched him against Slovenia a couple of weeks ago in Finland and he was excellent - and that's at international level. He can play the lone striker, he can play with a partner. He's got so many facets to his game."

However, Pukki struggled to make any real impact over his 26 Scottish Premiership appearances during his debut campaign, as, despite scoring seven goals and registering two assists in the league, the forward was handed just 13 starts by Lennon.

And, after being loaned out to Brondby IF in September of 2014, his 2013/13 campaign would prove to be the centre-forward's only full season at Parkhead, with the Danish side making his temporary switch a £608k permanent deal the following summer.

However, while hindsight is a wonderful thing, Celtic's short-sightedness regarding Pukki's ability has been rather embarrassingly highlighted since the Finn's 2018 move to Norwich City.

Indeed, over his 138 appearances in all competitions for the Canaries, the now-31-year-old has scored a rather remarkable 70 goals and registered a further 17 assists for the club - with 14 of these goals and three of the assists coming in the Premier League.

As such, Peter Lawwell's decision to cash in on the £6.3m-rated striker for over 10 times less than this figure back in 2015 has proven to be something of a nightmare deal for the former Celtic chief executive, as, not only could the Bhoys have used a player of Pukki's goalscoring ability last season, the club are also at least £5.6m out of pocket on the man Daniel Farke dubbed an "unplayable" talent.

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