Kalidou Koulibaly has struggled since his move to Chelsea (Photo: Getty)

Frank Leboeuf says he is ‘stunned’ with how poor Kalidou Koulibaly has been this season, ahead of Chelsea’s clash with Liverpool on Saturday.

The game at Anfield between the two struggling sides has been touted as pivotal in the race for the top four, with defeat potentially ending their chances of qualifying for the Champions League.

Many of Chelsea’s players have struggled this season but Koulibaly’s poor form has been particularly notable given his strong reputation prior to moving to Stamford Bridge last summer.

Considered by many to be one of the best centre-backs in the world while at Napoli, the 31-year-old looks out of his depth in the Premier League, much to the disappoint of fans including Leboeuf.

‘I’m as stunned as everyone else. I was so happy when he signed,’ the former Blues defender wrote in a column for Chelsea News.

‘I said, “Yes, that’s the player we need – strong, leader at the back for Napoli, great player, great mentality, alongside Thiago Silva, wow, that’s going to be fantastic”.

‘I think Kalidou Koulibaly will be the first one to admit his disappointment. We are all disappointed, because he hasn’t yet fulfilled any expectations. The fact that behind him though, the goalkeepers do not provide too much security with their form lately, doesn’t help.

Koulibaly was considered one of the best centre-backs in the world at Napoli (Photo: Getty)

‘But still, I really thought that Chelsea had one of the best central defences this summer with Wesley Fofana, Silva, Trevoh Chalobah, and Koulibaly. But it’s not what’s happened and I’m sad about that.

‘Sometimes it takes time to settle in. It was easy for me, I can’t explain why, but I felt so good so early during my time at Chelsea.

‘But sometimes it takes longer for some players to settle down, and if Chelsea have time and try to organise everything, and maybe Kalidou next season is going to be fantastic and show the world that he is still the player Chelsea signed from Napoli.

Liverpool take on Chelsea on Saturday (Photo: Visionhaus)

‘I have doubts though and we are all disappointed. I want to believe it’s not the end of it, you don’t lose all your tools like that, it’s impossible. It’s just mentally that he has to fix some stuff, maybe with his family. I think we have to give him a chance to show the world that he’s still a good player.’

Koulibaly was dropped for Chelsea’s last game against Crystal Palace in favour of new signing Benoit Badiashile and it remains to be seen if he will return to the starting XI for the Liverpool clash.

‘If there is one team more sick than Chelsea right now, it’s Liverpool. In terms of big clubs trying to heal, Liverpool are there with Chelsea,’ Leboeuf added.

‘Liverpool have dropped it’s football so quickly. Defensively where they were so strong, they don’t exist anymore. Offensively they don’t score as many goals.

‘It’s a great time for Chelsea to play Liverpool for sure, and show to the world that you are healing better than Liverpool and you are on your way back to your best. It’s going to be a very interesting game, to see how the two teams react.

‘For me, everything works in their heads. Whoever is going to be the strongest mentally and psychologically is going to win the game. We are going to see the doubts of both teams, and they could concede a foul or give the ball away and then suddenly, you will see the doubt. That can make the difference.’

MORE : Graham Potter explains the real reason why Marc Cucurella is struggling at Chelsea

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‘I have doubts and we are all disappointed.’