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It really is out with the old and in with the new at Celtic.

On the same day that Marco Tilio was officially announced as the club’s newest member of the Celtic-Australia contingent, another of its. cast left in the shape of Aaron Mooy. The 32-year-old, who signed last summer, confirmed that he would be retiring from both international and club football immediately following reports about his failed attempts to shake off a persistent back injury.

In a statement, Mooy said: "While it feels really sad to be leaving the game, I just feel the time is right for me. I have been so fortunate to enjoy such a great career across the last 15 years, creating some fantastic memories. I am delighted to finish my career on such a high with Celtic and I would like to thank all the fans for the great support they gave me during the past year - I was delighted to be part of such a memorable season.

"I hope Celtic continue to dominate the game and I wish Brendan, the new manager, great success with the great group of lads at the club."

While Mooy only spent one season at the club, his impact on the team during that time was significant. Making 42 appearances in all competitions, the midfielder played a key role in ensuring that Ange Postecoglou's second and final campaign in charge was a successful one.

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Of course, there were many doubters when he first joined. Mooy had been plying his trade in the Chinese Super League for two years, with a lengthy break between his last club match at Shanghai Port and his first game with Celtic.

The swirling questions were not related to how good a player he was, his time down south at Huddersfield Town and Brighton proved that. They were instead circulating due to the level he was playing at, coupled with his age when joining the club.

Having been linked with the club the summer before, Mooy was a year older at 31 when he finally arrived. Could he keep up with the physicality of the Scottish league while being able to mix it with the big guns in European competition?

For at least one of these questions, the answer was an emphatic yes. After a slow start to his Celtic career, including a dismal 45 minutes in an away defeat to St Mirren, he began to gain some momentum.

This came last October, following his second start in the league against Hibernian, where the midfielder managed to assist two goals in what was an impressive 6-1 win for the Hoops. Following this, Mooy was given the nod to start against Hearts at Tynecastle, where he played the full 90 minutes as he assisted a Giorgos Giakoumakis header from a corner. Another goal contribution from the midfielder in what was a vital 4-3 victory on the road.

Despite these assists, as well as some great individual performances to boot, it would take Mooy until December 28 to break his goalscoring duck for Celtic.

He was able to score two goals, one from open play and the other from the spot, as his patience was rewarded with a brace at Easter Road against Hibs.

He had played every minute for Australia at the 2022 World Cup in Qatar, mixing it with Kylian Mbappe and Lionel Messi, respectively, as he guided his nation to the Round of 16. Mooy had effectively used the biggest football competition in the world as a warm-weather pre-season, and the results in terms of improvement were stark.

He was pivotal in Celtic winning all three domestic trophies during his time at the club. His passes to Greg Taylor and Reo Hatate in the lead-up to both of Kyogo Furuhashi’s goals in the League Cup final against Rangers were key in retaining that piece of silverware.

READ MORE: Why Celtic signing Marco Tilio is an instant starter

Despite his perceived laid-back approach and lack of speed, what was perhaps most impressive about Mooy at Celtic was his footballing IQ and the speed with which he could play intricate passes to break the opposition lines. He could find a way to influence or change a game and the ball was safe in his possession at all times in the process.

Much like the League Cup, Mooy also imposed his influence on the Scottish Cup too. Scoring three times as well as assisting once, he started every match he featured in up until the final, where he was ruled out with the same injury that caused his early retirement.

His final appearance ultimately came against Rangers in the 1-0 Scottish Cup semi-final win. A fitting way to bow out, though he did not know it at the time. The term cult hero is often overused, but Mooy typifies the very definition of that phrase. By going out on a high with a domestic treble secured, he will be fondly remembered by the fans.

Mooy was a regular goal contributor for the Celtic, who was not afraid to get physical when those necessary situations arose. Because of this, he leaves the footballing stage a winner, with his freshly filled trophy cabinet a fairer reflection of the career he has had thanks to his time in Scotland.

This piece is an extract from the latest Celtic Digest newsletter, which is emailed out every weekday evening with a round-up of the day's top stories and exclusive analysis from The Celtic Way team.

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