Manchester City head coach Josep Guardiola has called former Liverpool head coach Jurgen Klopp the toughest opponent of his career. Sport24.az reports that the Spanish expert made a statement about this to Marca:
"Liverpool, led by Klopp, was the biggest test of my coaching career. He always gave me a headache. I, along with my coaching staff, drew up plans on how to stop him. There have been times when I thought "I did it", but the next day I was disappointed."
Note that Klopp coached Liverpool between 2015 and 2024. The Reds won the Premier League and the Champions League under his leadership.