John Terry thought Koulibaly's 'courtesy call' was a prank call

Since

departed at the end of the 2016-17 season the shirt was unofficially retired as no first-team player at

has worn 26 after Terry. Koulibaly reveals John Terry thought his courtesy call for the shirt number was a prank caller and hung up on Chelsea's new centre-back. Terry eventually happily gave his blessing as he will wear the number 26 next season at Chelsea as well.

said:

"I was nervous a bit because I was waiting to sign my contract in Chelsea. It happened the day before. I was happy, and the second thing is I wanted to know which number was free.

"Speaking with the team manager, he told me some numbers, and he didn't tell me the 26. I said that John left it in 2017 and nobody took it from this time. So I was asking myself if it was retired or maybe nobody wanted to take it."

Koulibaly revealed it was the former

and Chelsea hero,

, who gave him John Terry's phone number.

"I asked Gianfranco Zola, who I know very well, about the club, about the structure and the supporters, and I asked him for John's number because I wanted to ask for the jersey,"

Koulibaly said.

"I called him and at the beginning he didn't believe that it was me, he believed it was a joke. He put down the phone and called the team manager to ask if it was really me.

"I know that it's a very important number for him, and it's very important for me because I took it to Napoli and I wanted to keep it for here at Chelsea.

"When he told me 'yes', I was really happy because I know what he did for the club and the supporters and the city here, and I knew it was important to ask him. He gave me his answer and I was happy.

"I wanted to tell people I had asked him before, because I didn't want to be disrespectful to a legend of the club."

Chelsea will kick off their Premier League season on Saturday against 

.

"

This team is a fantastic team of winners, of big stuff. I want to give them everything on the pitch,"

Koulibaly added.

"I'm 31 with a good club in a good city. I hope I will stay here a long time."

"I will try to do my best and try to give solidity to the team. I know it will be difficult because I come from Italy and Premier League football is difficult. But I'm very motivated and want to show everybody Chelsea made a good choice with me."

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