It is commonly accepted that the best managers in sports need a ruthless side when it comes to their players.

For Ange Postecoglou this summer, this side will have to come to the fore as Celtic look to take strides in the Champions League.

Their place was confirmed officially when they clinched the title last Sunday against Hearts at Tynecastle, with the country’s coefficient ensuring that an automatic group stage berth awaits them.

Despite some encouraging performances on European football’s biggest stage, Celtic only managed to accumulate two points in this season’s competition.

While the team’s domestic dominance is not in question and deserves massive praise, it is clear that some playing personnel changes have to be made in order for the squad to progress in Europe.

Stage One: Clearing the deadwood currently on loan

Celtic Way: Albian Ajeti Albian Ajeti (Image: SNS)

First and foremost, there has to be a clear-out of the players not contributing to the team on a regular basis. Some of the men on loan such as Vasilis Barkas, Ismaila Soro, Yosuke Ideguchi and Albian Ajeti were high-profile signings that have not worked out for a multitude of reasons and should be moved on. It is an added bonus if you recoup any of the fees involved in bringing them to the club, as their valuations have dropped since their arrival. This is not to say that the individuals named will not have decent careers outside of Celtic, but if the club aspire to be a force in the Champions League, then budget will have to be freed up by removing those who have not fit the Postecoglou model.

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Furthermore, it is clear that some of the younger players out on loan such as Osaze Urhoghide and Liam Shaw are unlikely to make the required grade at Celtic, and their availability for transfer should be made known to teams down south and abroad. Another is Liam Scales, and if Aberdeen can find the cash, then no one at Parkhead should not stand in the way of a permanent deal.

Players such as Mikey Johnston and Adam Montgomery will get a chance in pre-season, but their long-term careers are also in doubt. Talent and previous impact on the first team only gets you so far, especially under this manager. Johnston, in particular, has shown glimpses of brilliance, but his inconsistency and sketchy injury-record likely point to a departure in the future.

Stage Two: Necessary first-team departures

Celtic Way: David TurnbullDavid Turnbull (Image: SNS)

Now we're getting to the nitty-gritty and where Postecoglou needs to be especially ruthless. It starts with the goalkeepers. Despite signing last summer, Benjamin Siegrist has failed to displace Scott Bain on the bench. The former Dundee goalie seems happy being the backup to Joe Hart, but is that good enough for Celtic’s lofty European aspirations? Both men could leave the club, freeing up a space for a goalkeeper coming through the ranks from the youth set-up, and another who could challenge Hart for the number one jersey.

As good as the Englishman has been, Celtic must begin forward-planning for life without him by investing in a young goalkeeper capable of playing with the ball at his feet - not Hart’s strength.

Another central defender will be needed ahead of next season, as Stephen Welsh will more than likely leave in search of first-team opportunities. Left-back may be another position looking to be strengthened. Alexandro Bernabei has had little time on the park, and his performances have not really suggested that he will displace Greg Taylor anytime soon. Will he want to stick it out so far from home under these circumstances? One to keep an eye on.

Despite the fanfare that surrounded him when he eventually arrived at Celtic in 2020, David Turnbull has been on the periphery this season. He has undoubted talent but given the impact he made previously, a respectable fee from a club down south may be the best option for a gifted footballer - begrudgingly.

Celtic’s forgotten man James McCarthy – yes, he is still employed by the club – is into his second year of a FOUR year deal. With an evident lack of suitors for the midfielder’s services, his should be torn up in the summer. What is abundantly clear is that Postecoglou doesn't fancy the player, as his sparingly low minutes on the park would attest. Celtic cannot afford to have passengers in the squad, and let's be honest, that's what McCarthy is.

In the attacking areas, Celtic rotate players frequently, so there is less need to get bodies out the door. James Forrest signed a new three-year deal last season but may want more game time given his advancing years. He might struggle to find a take who would match his salary though which could be a complicating factor, especially if he wants to stay in Scotland. If interest in Israeli winger Liel Abada firms up, as has been reported in recent months, then he may be the player to cash in on.

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Stage Three: Strengthen the current squad

Celtic Way: Ange Postecoglou has shown what he can do when backed to succeedAnge Postecoglou has shown what he can do when backed to succeed (Image: SNS)

Celtic are in an enviable position where the squad is in a very strong state. The strength in depth that the team has is pleasing, with the vast majority of players at an age where their prime is still yet to come, hopefully under the guidance of Postecoglou.

Despite this positive development, the club have got to strike whilst the iron is hot and recruit accordingly in order to improve the team further. The financial benefits just from participating in the Champions League will increase the likelihood of better-quality players joining the club which will in turn improve the team as a whole going forward.

Celtic’s record transfer spend on an individual is Odsonne Edouard - the club forked out over eight million pounds for the young Frenchman’s services. Despite Postecoglou opting to unearth gems from different parts of the world, the Australian has surely worked up enough credit in the bank to be afforded an Edouard sized outlay on a marquee signing if that is what he desires.

An established player available to Celtic could potentially be the difference between drawing and winning a game in the Champions League, which in turn brings financial benefits thanks to prize money. By having a game-changer at his disposal, Postecoglou could take Celtic to new heights.

This type of player could come in the shape of a progressive goalkeeper who is good with the ball at his feet, an attacking midfielder that can complement the likes of Reo Hatate and Callum McGregor or a striker who can terrorise foreign defences on any given night in the Champions League.

It is important that Postecoglou has the sufficient resources and tools required to do as well as he can on the biggest stage for Celtic. To do that, it may well be as much about those going out as those coming in.