Australian Nick Kyrgios has been banned for eight weeks and fined $25,000 (£20,560) by the ATP for his behaviour – including “lack of best efforts” – in last week’s Shanghai Masters.
The 21-year-old patted the ball over the net several times when serving in his 6-3 6-1 defeat by Mischa Zverev.
He also began walking back to his chair before a Zverev serve had landed.
World number 14 Kyrgios said he was “truly sorry” and would “use this time off to improve on and off the court”.
He added: “I regret that my year is ending this way. I do understand and respect the decision by the ATP.
“The season has been a long one as I battled several injuries and other challenges towards the end of the summer.
“My body finally just gave out in Shanghai both physically and mentally.
“This is no excuse, and I know very well that I need to apologise to the fans.”
Kyrgios’ suspension is set to end on Sunday, 15 January 2017.
But the ATP, the governing body for men’s tennis, said the ban would be reduced to three weeks if Kyrgios agrees to “a plan of care under the direction of a sports psychologist”.
During the second-round match with Zverev, Kyrgios also argued with a fan and received a code violation for swearing, after which he was fined $16,500 (£13,546) for breaching the ATP code of conduct.
Last week British world number two Andy Murray said he was “not convinced” a fine was the best solution.
“Sometimes players do need protecting. Sometimes he goes into press and says things he regrets,” said the Scot.
“In those situations he maybe needs to be guided a little bit better.”
World number one Novak Djokovic has said: “I share the opinion of many players and many people in the tennis world that he’s one of the greatest talents the game has seen lately.”
In 2015, Kyrgios was banned for 28 days and fined $25,000 for insulting Stan Wawrinka during a Rogers Cup match in Montreal.
He was also criticised for his displays at Wimbledon and the US Open, and withdrew from Rio 2016 following a row with the Australian Olympic Committee.