Bernard Tomic has been dumped by racket sponsors Head just hours after he was fined more than £11,000 following his controversial first-round exit from Wimbledon.
The Australian was beaten in straight sets by Mischa Zverev on Tuesday and then gave an extraordinary press conference, saying he felt "bored" during the match.
Tomic also admitted he called for the trainer even though he was not injured to try to disrupt his opponent's momentum.
It has resulted in a fine of 15,000 US dollars (£11,600) from the International Tennis Federation, a significant chunk of his £35,000 earnings from the tournament.
The 24-year-old's level of effort has frequently been called into question, and he said on Tuesday: "I couldn't care less if I make a fourth round at the US Open or I lose first round.
"To me, everything is the same. I'm going to play another 10 years, and I know after my career I won't have to work again."
News of the fine was followed by a statement from Head, who stood firmly behind Maria Sharapova during her doping ban but have deemed Tomic's attitude unacceptable.
A statement on www.head.com read: "We were extremely disappointed with the statements made at Wimbledon by one of our sponsored athletes, Bernard Tomic.
"His opinions in no way reflect our own attitude for tennis, our passion, professionalism and respect for the game. Therefore, we have decided to discontinue our collaboration with Bernard Tomic."
The official reason given for Tomic's ITF fine was unsportsmanlike conduct, with the same offence costing Russia's Daniil Medvedev 14,500 dollars (£11,200).
Medvedev had a number of disputes with umpire Mariana Alves during his five-set loss to Ruben Bemelmans in the second round and ended the match by throwing coins in the direction of her chair.
He expressed remorse afterwards and insisted he was not trying to insinuate that Alves had been bribed but his conduct cost him 7,500 dollars.
The remainder was for two offences during the match, including being docked a point after a heated argument with Alves.
Medvedev earned £57,000 for reaching the second round.
It is not the first time Medvedev, who knocked out Stan Wawrinka in the first round, has been in hot water over his conduct towards officials.
At a second-tier event last year, the 21-year-old was defaulted from a match after saying umpire Sandy French was "friends" with his opponent Donald Young. Both are black.
Medvedev denied he intended to be racist, claiming it was a misunderstanding.