Back in June 2016 when Brendan Rodgers was unveiled to much fanfare inside Celtic Park, Leigh Griffiths cut a relaxed figure as he engaged with the 13,000 fans who had turned up on that balmy Monday evening.

Cavorting and posing with the Championship trophy, Griffiths – the only player on view and on the back of a season in which he had netted 40 goals – had quite the reason for the chilled demeanour as a new boss entered the fray.

Except he didn’t. As a new broom swept clean Moussa Dembele arrived and all of a sudden there was a fight for the striker’s berth. Griffiths didn’t fall entirely out of the picture – that came later - but he certainly faded from the front and centre view.

It has been interesting this week to note the arrival of Benjamin Siegrist as a rival to Joe Hart for the gloves at Celtic. There is no correlation between Griffiths and the goalkeeper other than the fact that Hart too might well have fancied himself as a fairly safe bet to make the starting XI every week.

Performances aside, Hart endeared himself quickly to the Celtic support with leadership and experience but also by allowing enough of his personality to come through in his interactions with the club’s support. He has not quite had a summer to rival Jota in terms of his passport stamps but he has enjoyed a decent break after being one of the perennials on the teamsheet throughout his inaugural campaign in Glasgow.

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Siegrist, articulate and intelligent with ample experience behind him, was respectful and complimentary about Hart when he was unveiled as Celtic’s third signing of the summer this week. The Swiss keeper, though, will fully fancy himself as capable of pushing Hart for the starting spot with the competition between the two an intriguing tussle.

Hart is clearly number one – literally and figuratively – but there are few competitive sportspeople who sign four-year contracts expecting to be second fiddle throughout.

Aside from the obvious observations to be drawn about two goalkeepers genuinely vying for the same spot was something else of note. With Scott Bain – who also recently signed a new contract with Celtic that ties him at the club until 2024 – and Conor Hazard – out on loan but still tied to the club – there is a clear inference on who is making the decisions in terms of signing players.

Ange Postecoglou holds all the aces on that front. The Greek-Australian has spent what money he has wisely and can point to both transfer windows that he has operated in as being used to make Celtic’s pool stronger coming out of it.

Given the activity that has gone on in the opening stages of this window, the likelihood of further strengthening appears significant given the trust he has quickly earned.

Harry Kewell has bolstered the backroom staff with Postecoglou clearly identifying the 43-year-old as another addition who will have a role to play in the season that lies ahead.

What will be most interesting is just how Celtic line up for the start of that new campaign.