Celtic knew that they had to deal without having Hyun-jun Yang for a period of matches after he went away on international duty with South Korea earlier this month.

Unfortunately, Haissem Hassan was unable to start against Rangers on Sunday because he had issues overnight and was unable to get enough sleep to play from the start.

That meant that Sebastian Tounekti had to start on the left flank for the Scottish giants in the League Cup quarter-final clash, with Camilo Duran on the opposite flank.

The Tunisia international has been struggling at the top end of the pitch in the 2026/27 campaign, and those struggles continued against Rangers on Sunday.

Why Sebastian Tounekti should not have started against Rangers

Tounekti played the opening 45 minutes of the 3-0 loss to Rangers and did not make any noticeable impact on the match, with no crosses, no shots, and no chances created.

The former Hammarby star played it safe far too often, going back to Kieran Tierney or Liam Scales on the left side of the defence, instead of attempting to take Dujon Sterling on in the final third.

Tounekti had to be taken off at half-time due to his lack of impact, but that was an outcome that could have been predicted before a ball had been kicked in the game, due to his poor form.

The Tunisian forward has gone 16 games without a goal in the Scottish Premiership and 15 matches without an assist in all competitions for the club, despite playing as a winger.

Instead of starting Tounekti on the left wing, Martin O'Neill could have played Benjamin Nygren on the right wing, moved Duran over to the left, and beefed up the midfield with Alex Oxlade-Chamberlain or Oliver Sorensen.

Celtic flop was even worse than Tounekti

Despite being subbed off at half-time, the left-sided attacker was not the worst performer on the pitch for the Hoops in their frustrating defeat to Rangers on Sunday.

Celtic started with Tounekti on the left, Duran on the right, and Nygren in the number ten role behind Kasper Hogh as the starting number nine at Ibrox.

The Scottish giants splashed out a club-record fee of £11m to sign the Denmark international from Bodo/Glimt in the summer, but he is already looking like their biggest waste of money since Adam Idah was signed from Norwich City for £9.5m.

During his time at Parkhead, the Ireland international scored 29 goals in 76 matches before being sold to Swansea City for £6m, just 12 months after being bought for £9.5m.

Hogh's current form for Celtic suggests that he could be on course to follow in Idah's footsteps because his lack of consistency has been a real concern this season.

The Dane, who was handed a 3/10 player rating by FFC for his performance, struggled throughout his time on the pitch against Rangers, most notably tripping over his own feet after Colby Donovan played a delightful ball over the top to him.,

Hogh would have had a one-on-one opportunity in the box if he had kept his composure and controlled the ball in that situation, only for him to gift the ball back to the hosts instead.

The 25-year-old marksman played 64 minutes, which meant that he was given more time to impress than Tounekti, but failed to make any meaningful contribution to the team.

Celtic's biggest opportunity of the match was Donovan's switch to the striker when the score was 0-0, but he lacked the quality or composure to bring the ball down and score.

Hogh's only goals for the Hoops so far came when he scored a hat-trick against Kilmarnock in his second appearance for the club, and he has not scored or provided an assist in five appearances since.

As was the case when they paid £9.5m for Idah, Celtic splashed £11m on Hogh in the hope that he would be a reliable and consistent goalscorer to lead the line for O'Neill's side.

Unfortunately, his start to life at Parkhead suggests that he does not have the consistency or quality to be that player for the Hoops, which is why he may end up going down as the club's biggest waste of money since Idah.