Trippier left Atletico in January for Newcastle.
He told BBC Sport: "I was excited to go play for him. What you see on the touchline is what he does every day in training. He is very emotional, obsessive.
"There were times when I was in bed, already asleep, and he would call me on the phone. It's crazy, I had never experienced it with another coach. He would talk to me about things that I could improve and I was trying to sleep. I would receive messages random text calls from him talking about football. You can see he's obsessed. He's an amazing coach. Emotional is the word.
"He is crazy about football. His documentary perfectly shows what he is like every day. He is an incredible coach and I am very lucky to have worked with him because I learned a lot."
On training, Trippier added: "They were crushing, crazy. He's one of those trainers who wants you to run through a brick wall for him. If you don't work hard, you're going to be out. He doesn't care how good you are or what your name is. You have to run.
"In training, it doesn't matter if it's the warm-up or the rondos, if you don't do everything the right way, he'll let you know. It's exactly the same as on the sideline. He's relentless, but unbelievable."
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