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When you think of Ange Postecoglou’s most successful signings for Celtic, your mind automatically jumps to examples such as Kyogo Furuhashi, Jota or Cameron Carter-Vickers.

Indeed, while these high-profile acquisitions were all shrewd pieces of business, none of these perhaps addressed a problem area like the signing of ex-England international Joe Hart from Tottenham Hotspur.

Celtic had used three different goalkeepers in the previous season, with none of Vasilis Barkas, Scott Bain or Conor Hazard particularly impressing when given the chance between the sticks. Stability was sought after in this position, and it was Hart who the club turned to for this.

Over 100 appearances in all competitions later, and there is no doubt as to who the number one goalkeeper in the Celtic side is. He has been an inspired signing, plugging a gaping hole in the last line of defence for the team since his arrival.

This makes it all the more difficult to admit that Celtic should be planning for life after the 36-year-old immediately, starting in the summer transfer window. Despite Hart’s stellar contributions to the club over the past two seasons, it is now time for a more youthful goalkeeper to take his place.

Many quarters thought that this might have been summer signing Benjamin Siegrist, but the Swiss goalkeeper has failed to break back into the side since returning from injury, not appearing in any matchday squads since December of last year. Thanks to this, Hart has been an unopposed automatic starter for Celtic, with Bain very much the backup option on the bench.

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If age is one factor which will be considered when identifying the need for Hart’s replacement, then the ability to play out from the back must also be key in scouting his successor. In an ever-changing footballing landscape where goalkeepers are now expected to regularly make passes both inside and outside the box, scouting a player that has the ability to do this will be mightily important, especially for Postecoglou’s ever-evolving system.

Hart is part of the last generation of goalkeepers who were not expected to do this in their positional role. Effectively gone are the days of shot-stoppers’ job being just to keep the ball out of the net. Top goalkeepers nowadays have to be able to undertake this role, or the elite clubs will not be interested in them, as brutal as that may be.

Hart’s limitations in playing from the back were clear to see in the Champions League this season, particularly against RB Leipzig in Germany. With the game finely poised at 1-1, Hart makes a horrendous pass from the back to an unmarked Leipzig attacker, who easily played the ball to his team-mate and put it past the red-faced goalkeeper. In fixtures that are decided by small margins, this mistake was fatal, both individually for Hart and collectively for Celtic’s Champions League aspirations.

Recently, we have seen Celtic delve into many different markets around the world, in continents such as North and South America, Asia and Europe. In particular, South America has been a hotspot for ball-playing goalkeepers in recent times, and one which the club should be looking to tap into.

Footballing institutions who are moderately similar to Celtic in terms of size such as Benfica and Roma directly benefitted from this market, both on and off the pitch, with their signings of Ederson and Alisson Becker respectively. Both Brazil internationals were plying their trade in the native Serie A before being signed by their first overseas clubs.

Following impressive stints in their formative years adapting to European football, the two goalkeepers from the continent managed to secure big moves to the English Premier League in the form of Manchester City and Liverpool for a combined €115m, in turn netting Benfica and Roma enormous profits in their respective initial investments.

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These are two of the most high-profile success stories, but what is stopping Celtic from scouting the same countries in search of South America’s next great ball-playing goalkeeper?

Timing is key in this search, as teams from Portugal and Italy are far more attractive moves for young players than a switch to the Scottish Premiership, as harsh as that sounds. Celtic have got to approach these targets when a move to Glasgow is truly the best move for their development, and before teams of a higher domestic league standard come calling.

Thankfully, Celtic already have an expert in-house when it comes to South America in Mark Lawwell, who is the club’s Head of First Team Scouting and Recruitment. Lawwell, who was previously employed by the City Group, has experience scouting and working with players based in the continent, so you would expect no stone to be left unturned in searching for potential talent in those regions in his fairly new role at the club.

There is no doubt that Hart has been a great signing for Celtic, as his trophy haul will attest to that when he leaves the club, whenever that will be. However, sentimentality should never cloud the judgement of a player’s shortcomings in professional football, regardless of the success that he has evidently brought the club. As the club moves into the third phase of the Postecoglou revolution, the first steps must be taken to find his long-term successor.

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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