It hasn’t taken long for the doubters to come crawling out of the woodwork. 421 minutes to be precise.

That’s all the game-time that has been afforded to Adam Idah so far this season. Just two starts in the Scottish Premiership, one in the Scottish League Cup and one in the Champions League. The rest of his 11 appearances so far have been as a substitute.

His goal return is decent, considering the stop-start nature of his return to Scottish football so far – one for every 105 minutes on the pitch. There are a lot of forwards who would envy that record.

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The man who is currently denying Idah more time in the Celtic 11, Kyogo Furuhashi, is one of them. With eight of his 11 appearances so far coming as a starter, he has scored five times in his 674 minutes on the pitch.

That’s a goal every 135 minutes.

Yet when former Celtic striker John Hartson claimed ahead of Wednesday night’s Champions League game in Atalanta that Idah hadn’t “hit the ground running” on his return to Scotland, this time as a permanent signing, he cited the Japan striker’s form and status as a primary factor.

“One of the reasons,” Hartson said, “is that it’s very hard to dislodge Kyogo.”

Hartson went on: “I am not going to criticise him (Idah) too much, but I am not sure who else Celtic had their eye on last season.

“He cost £9 million. A lot of the fans might just say well ‘could we have got a better one? One of the reasons why Celtic took him is because he did so well on loan. He seemed the obvious one.”

It’s a little early to be asking such questions.

Just hours after Hartson’s comments, Idah was handed his first Champions League start by Brendan Rodgers. And he delivered a performance that showed just why the Bhoys boss coughed up so much money to get him from Norwich.

With the 7-1 drubbing against Borussia Dortmund still fresh in everyone’s minds, Celtic headed to Europa League champions Atalanta knowing that they would need to be more compact without the ball, and stronger with it.

Idah delivered on both counts during an energetic 68-minute display. His relentless tracking back put Atalanta under the kind of pressure that was non-existent in Dortmund. He did his bit in the opposition half too.

It was a night when Idah was always going to struggle to add to his goal tally, but there will be other occasions for that.

Reading some of the more clueless reactions on social media during and after the Atalanta game, you’d swear Idah had a nightmare in Italy, but his manager will have a different view.

Idah will prove his doubters wrong, just like his fellow Irishman Liam Scales. He is not the finished product. Far from it. There is so much scope for improvement, but you can see that it is in him to make those strides.

At just 23 years of age, he has mostly been deployed from the bench. Just over 30 percent of his league appearances so far for Norwich and Celtic have been as a starter (39 starts in 122 appearances).

It will take a little patience – on the part of both Idah and Celtic fans – but when those numbers go up, that’s when we will see the real Adam Idah.

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