Mesut Ozil has claimed Manchester United manager Jose Mourinho labelled him a "coward" when the pair were at Real Madrid.
The Arsenal midfielder has released a new autobiography in which he recalls a bust-up with Mourinho when the Portuguese was in charge at the Spanish giants.
Ozil and Mourinho won the La Liga title together during their three years at Real Madrid, both joining the club in 2010 and departing in 2013.
The book, Die Magie des Spiels (The Magic of the Game), which is being serialised in German newspaper Bild, details a heated exchange between the pair after an unspecified match in which Mourinho gave Ozil a dressing down over a complete lack of effort.
"You think two beautiful passes are enough," said Mourinho, as written by Ozil. "You think you're so good that 50 per cent is enough."
Ozil added: "He pauses. Stares at me with his dark brown eyes. I stare back. Like two boxers at the stare-down before the first round. He shows no emotion. Just waits for a response from me. How much I hate him right now. And I love Mourinho actually."
Mourinho continued tearing into Ozil after the German threw his shirt on the floor: "Oh, are you giving up now? You're such a coward.
"What do you want? To creep under the beautiful, warm shower? Shampoo your hair? To be alone? Or do you want to prove to your fellow players, the fans out there, and me, what you can do."
Despite their relationship becoming fractured over the course of their time at Real Madrid, Ozil has also revealed Mourinho was a big factor in his decision to sign for the club over Barcelona in 2010.
The 28-year-old had initially preferred a move to the Nou Camp, but claims then-Barcelona head coach Pep Guardiola was absent from discussions over a transfer, allowing Mourinho to swoop.
"Because of Guardiola's behaviour, I did not want to go to Barcelona," Ozil wrote.
"Especially because Mourinho fought so much at the same time. He was so convincing. So heartfelt, trying so hard. He was the complete opposite of the Barca coach. So I decided for Jose Mourinho and Real Madrid."