Stuttgart Open tournament organisers are investigating Nick Kyrgios's claims that he was racially abused during his semi-final loss to Andy Murray on Saturday.
Kyrgios and Murray were involved in an entertaining match where a tiebreak decided the opening set, after which the Australian lost his cool and received a points and game penalty as well as becoming involved in an argument with the chair umpire.
Kyrgios, who refused to play during the second set until the supervisor stepped in, lost 7-6(5), 6-2. He later revealed on Instagram that he had retaliated after hearing a racial slur.
"We stand for creating an inclusive environment for all players, staff members and visitors where discrimination of any kind is not tolerated. This attitude is lived by all people involved and responsible," organisers said in a statement on Sunday.
"These fundamental values are as important as values like fairness, tolerance and team spirit to us. Thus no discriminating actions by the spectators are accepted.
"We have expressed our regret towards Nick Kyrgios and his team and assured that any kind of discrimination is unacceptable. The incident is currently under investigation."
Murray plays Italy's Matteo Berrettini in the final later on Sunday as the Briton seeks his first ATP Tour title since winning at Antwerp in 2019.