Celtic have earned a strong reputation for developing and selling players for profit over the years, and added to that this summer with the sale of Arne Engels.

The Belgium midfielder was bought for £11m from Augsburg in the summer of 2021, before being sold to West Ham United for a fee of £22m this summer.

Matt O'Riley and Kieran Tierney were both sold for £25m in the past, to Brighton and Arsenal respectively, whilst Nicolas Kuhn was sold to Como for £16.5m last year and Daizen Maeda was sold to Ipswich for £10m this year.

As is the case with every club in world football, not every signing Celtic make works out for them. For example, one of their worst signings in recent times was their deal to bring Albian Ajeti to Parkhead in 2020.

How Albian Ajeti's career at Celtic unfolded

In the summer of 2020, Neil Lennon pushed to bring the Switzerland international to Celtic in a deal that cost the club a transfer fee of around £5m, after the striker had failed to establish himself with West Ham in the Premier League.

At the time of his move to Paradise, Ajeti was the third-most expensive centre-forward signing of all time, which put a lot of expectation around his output in front of goal.

Unfortunately, the Swiss forward only scored six goals in 30 appearances in all competitions for Lennon's side, with all six of those goals coming in the Scottish Premiership, as they finished second in the table that season.

Ange Postecoglou replaced Lennon in the dugout between the striker's first and second season at Parkhead, which resulted in him only playing 17 times, scoring twice, in the 2021/22 campaign.

After falling out of favour under the Australian coach, Ajeti went out on loan before being sold to Gaziantep for £500k, a substantial hit on the fee that was paid for him, after he failed to deliver goals on a regular basis during his time with Celtic.

Celtic forward is in danger of becoming the new Ajeti

Now, one of the club's current forwards is in danger of finding himself in the same position that Ajeti did after his struggles in Glasgow in his first 18 months at the club.

In the summer of 2025, Brendan Rodgers was aiming to improve the strength of his attacking options and swooped to sign Sebastian Tounekti from Hammarby for a fee of around £5.5m.

The Tunisia international put pen to paper on a five-year contract earning around £738,000 per year, per Swiss media, which means that, after 13 months in Glasgow, he has cost the club just over £6m so far.

Unfortunately, the Scottish giants have yet to get much value back for that £6m outlay on a transfer fee and wages, as he has failed to deliver consistent performances for Rodgers, Wilfried Nancy, or Martin O'Neill.

Celtic expect their wingers to provide goals and assists on a regular basis, as Jota did, as Maeda did, as Kuhn did, but that is not what Tounekti is doing.

The 24-year-old attacker has only scored two goals in the Premiership since the start of last season, and is yet to contribute with a goal or an assist in the current campaign.

Tounekti did not offer goals or assists on a regular basis in his first season in the Scottish top-flight, underperforming his xG, and that led to him losing his place in the starting line-up.

Hyun-jun Yang, who has scored two goals in his last two league games, started the season as the first-choice option on the left, but he went to the Asian Games before the 1-0 win over St. Johnstone.

Prior to that match, Celtic legend Scott Brown stated that Tounekti's output at Celtic has "not been good enough" and it is hard to argue with that assessment, as he has only scored two goals in 33 league appearances.

Like Ajeti, the Tunisian forward has failed to deliver consistent quality in the final third after being brought to the club for a significant sum of money, and it remains to be seen if he can turn things around.

If Tounekti continues to struggle over the next few months, Celtic may have a decision to make about his future, as they did with Ajeti after his first 18 months, because they need more quality from players in his position.

It currently looks like the £6m the Hoops have spent on him has gone straight down the drain, and it is down to the player to turn his fortunes around and change the narrative surrounding him at the moment.