While Ange Postecoglou's Celtic side endured a rather shaky start to their 2021/22 Scottish Premiership campaign, things have undoubtedly started to click under the leadership of the 56-year-old Hoops boss in recent months.

Indeed, a number of the Greek-Australian manager's summer signings have hit a run of excellent form, with Kyogo Furuhashi having scored 13 goals and registered three assists over his 18 appearances for the club, Benfica loanee Jota having bagged six goals and six assists over his 14 fixtures in green and white and Liel Abada having netted seven goals and provided five assists over 22 appearances for the Hoops.

However, while the argument could be made that any one of these three players have been Celtic's signing of the season, there is perhaps one summer addition who could be classified as something of an unsung hero at Parkhead - in the shape of Joe Hart.

Indeed, having arrived at Parkhead following two seasons in which the 34-year-old had played just 13 games of football, Hart has slotted into the role of Postecoglou's number one seamlessly, with the former England international's experience in the game bringing with it a sense of calmness and stability between the Celtic sticks that was desperately lacking last season.

This is an opinion that Chris Sutton clearly agrees with, as the former Bhoys centre-forward recently said of the shot-stopper: "I think he's done really really well. What he had strongly in his favour was [Vasilis] Barkas and [Scott] Bain have just been so poor in the Celtic goal and it was a low bar. But he's come in and it's been a massive boost.

"I think that he's brought a calmness and an authority at the back. You watched Celtic [last season], and with the greatest of respect to Barkas and Bain, every time they were in goal you thought Celtic are going to concede the goal. I don't feel the same with Joe Hart and I think that's an enormous deal. I think his experience has been important. I think he's been an enormous signing and a massive plus for Celtic."

Indeed, this is something that is reflected in the £1.8m-rated man's statistics, as, over his 12 Scottish Premiership appearances, Hart has kept six clean sheets, won 85% of his duels and made an average of 1.8 saves per game - with these returns seeing the 34-year-old average a highly impressive SofaScore match rating of 6.91.

As such, while Kyogo, Jota and Abada may well steal the headlines for Celtic, the veteran goalkeeper has undoubtedly been just as important for the Bhoys this season, as the £15k-per-week shot-stopper has been the rock which Postecoglou is building his side upon.

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