He's experienced action against both halves of the Glasgow divide - but it's Celtic who Florian Wirtz wants to know all about.
The rising German star made his comeback from injury against Rangers in a friendly earlier this season and has been touted for big moves across Europe. Another of his Bayer Leverkusen teammates who have been linked with transfers is Jeremie Frimpong, who joined the Bundesliga side in 2021 from Parkhead, the year which his good mate netted against Ange Postecoglou's team during a Europa League match at Parkhead.
A fruitful friendship has been struck up by the pair and it was Wirtz who helped the former Premiership right-back settle into life at Leverkusen. Both are now thriving under head coach Xabi Alonso but Frimpong told Relevo that his Celtic debut stunned him, and his pal had questions about the club. He said: "On a day-to-day basis, he (Wirtz) is exactly how he is seen on the pitch. He is impressive. He plays as if he had been there for 10 years. He's intelligent .
"He's also a great person, he was the first to take care of me when I arrived at the club. he was my first friend! 'Flo' asked me about Celtic, he invited me to his house, we would go out for dinner.
"He did things for make me feel at home. I don't know how to describe it, it was something almost unreal (his debut against Partick Thistle in 2019).
"Let's see if you understand me, when I touched the ball for the first time it was as if the ground was shaking. The atmosphere was spectacular, it was the best feeling you can have."
