Nick Kyrgios is being investigated by the ATP after branding the governing body "pretty corrupt" following his first-round win at the US Open.

Kyrgios was quizzed about the hefty fine of nearly £100,000 he was handed following his behaviour at the Cincinnati Masters earlier this month.

The volatile Australian smashed two rackets and was abusive towards umpire Fergus Murphy during his defeat by Karen Khachanov.

He told reporters at Flushing Meadows: "ATP's pretty corrupt anyway, so I'm not fussed about it at all."

The 24-year-old could now face a further fine or possibly a suspension.

An ATP statement read: "The comments made by Nick Kyrgios after his first-round match in New York will be assessed under the player major offence provision under ATP Rules.

"A determination will be made by Gayle David Bradshaw, executive vice president, rules and competition, following an investigation as required by ATP rules."

Kyrgios, who beat American Steve Johnson in straight sets to reach the second round in New York, later sought to clarify his comments.

In a statement on Twitter, he wrote: "It was not the correct choice of words and my point and intention was to address what I see as double standards rather than corruption.

"I know my behaviour has at times been controversial and that has landed me in trouble, which at times is granted and valid but my issue is around others whether gaining the same, less of more media attention doing the same or similar behaviour and not being sanctioned."