Celtic's recruitment in recent times has come under heavy criticism and for good reason. Most of the signings they have made over the past few years have proven to be ineffective. They have either left already or don't seem to have a future at Parkhead.

That was not the case with the club's recruitment during the Ange Postecoglou era though. In fact, it was one of their most fruitful times when it comes to talent identification. Over the course of two seasons, they were able to bring in Jota, Matt O'Riley, Kyogo, Reo Hatate, Josip Juranovic, Giorgos Giakoumakis, Carl Starfelt, Cameron Carter-Vickers, and more.

A ton of them ended up playing vital roles in the Celtic starting XI. Even those who did not, like Tomoki Iwata and Oh Hyeon-gyu, have proven themselves as quality players since leaving the club.

So, could Celtic be looking back at some of the transfer targets they missed out on during the Postecoglou era?

According to Voetbal 24, Celtic and Club Brugge are showing interest in Australian goalkeeper Mathew Ryan.

Those with a keen memory will remember that Celtic were linked with Ryan on more than one occasion back when Postecoglou was the manager of the club. Of course, the manager will have known the goalkeeper well from there time together in Australia.

Ryan became an integral part of the Australian national team with Postecoglou as the Socceroos' manager. Since then, he has gone on to make more than 100 appearances for them internationally.

It is also worth mentioning that Celtic will need to sign a goalkeeper in the summer. Kasper Schmeichel is set to leave at the end of his contract. And there is uncertainty whether Viljami Sinisalo is going to be the long-term first-choice between the posts or not.

Ryan is 34 years old. Some Celtic fans might raise their eyebrows at the idea of signing him. But he is still playing as a starter at the La Liga level for Levante.

So, if Celtic do end up signing Ryan in the summer, they would not be bringing in somebody who is playing in a lower division or has found himself warming the bench. No, they would be getting somebody who is the first-choice goalkeeper of a La Liga team.

Celtic are no strangers to bringing in veteran goalkeepers and handing them the first-team gloves. Could Ryan follow in the footsteps of Joe Hart and Schmeichel?

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