Sampdoria forward Fabio Quagliarella says Antonio Conte's training sessions are "back-breaking," but added that the Chelsea manager is a tactical genius.
Quagliarella worked under Conte at Juventus between 2011 and 2014, winning three straight Scudettos together.
While it was a successful time, the former Italy international said it was also a gruelling time with Conte one of the most demanding coaches he has ever worked for.
"With Conte, it was back-breaking both in training and in games," Quagliarella told Mediaset television. "The intensity was so high, and you could see that also in our games. He is phenomenal in the way he prepares you tactically.
"There were a lot of rules to adhere to -- if he gave us a day off, we weren't allowed out of Turin. He got angry very often -- very, very often."
Quagliarella was not a regular starter under Conte at Juve, though, and he joked how he once tried to convince Conte to give him more of a game.
"He had kept us for half an hour after training and as soon as we left, I was angry too," he said. "It was after a defeat to AC Milan and, as we left, I asked him to mix his numbers a bit because the No. 27, which was mine, always came out."
Quagliarella also praised for Watford manager Walter Mazzarri, his coach during his first spell at Sampdoria, and said that he has picked up so many tips during his playing career that he would like to go into management when he retires from playing.
"I've been lucky to have worked for many great coaches," he said. "They've all been so good that maybe at the end of my career, I'll give it a go myself."