Lewis Hamilton "doesn't seem to be bothered about losing" and could be replaced at Mercedes by "fed up" chief Toto Wolff, according to Bernie Ecclestone.
Hamilton, 37, is enduring one of the toughest seasons of his career with Mercedes unable to compete with Red Bull and Ferrari at the front of the grid. Instead, he and new team-mate George Russell are scrapping for podiums whenever a quicker car has a mechanical issue.
Russell has impressed by finishing in the top five of all nine races so far this season, while Hamilton's form has been slightly more erratic. Former Formula 1 supremo Ecclestone is unimpressed by that from the seven-time world champion, and believes Mercedes chief Wolff could end his £40m-per-year contract early.
"Lewis might sell his position to Toto," the 91-year-old suggested to the Daily Mail. "This is how much I am getting, I'll step down and give me half of what I would get. Toto can go and do one of his magic deals, offer someone less money and keep £20m.
"Nobody needs to tell Toto this because he has already thought of it. Lewis would probably stop under those circumstances. I don't know what he is doing dressing up in all those funny clothes. Has he a deal to it? Is it to get noticed? Maybe that's it."
He continued: "I didn't think [Russell] was that good but he has done an excellent job. I'm surprised. Or is it a case of Lewis doing a bad job? A bit of both. Toto is getting a bit fed up with Lewis. I don't think he's trying, do you? Let's put it another way, Lewis doesn't seem bothered about losing.
"It's not like him. He has a competitive nature but he's taking losing a bit easy for my liking. I don't think he is actively helping George. I don't think he's doing anything. I don't think he cares too much. He's not prepared to put the effort into winning that he did."
Ecclestone went on to suggest Hamilton had been faking the back pain that he demonstrated after climbing out of his Mercedes at the end of the Azerbaijan Grand Prix. The Briton had talked about the agony that had been caused by the car's porpoising, but this was dismissed as "bull****".
"George is taller and if it was going to happen to anyone it would have happened to him," Ecclestone added. "There was a bit of Nigel Mansell about it. At least with Nigel, he would get out of the car and rub his left leg as if he had broken it. Next moment, it would be his right leg."