Nick Kyrgios called on the ATP Tour to "get new people" after a furious outburst at the umpire in his defeat to Jannik Sinner at the Miami Open.

Kyrgios berated umpire Carlos Bernardes after his walkie-talkie went off mid-point during the first set.

The Australian was heard to label Bernardes "an absolute clown".

He subsequently added: "This is one of the biggest tournaments and you guys can't do your job. It's embarrassing.”

"You wonder why no one watches this sport. It's a laughing stock."

After receiving a code violation for an audible obscenity, Kyrgios was then handed a point penalty for unsportsmanlike conduct in the first set tie-break.

Kyrgios had been appearing to talk with a friend in attendance courtside, with that penalty further infuriating him.

"What's unsportsmanlike? What is unsportsmanlike?" Kyrgios asked of Bernardes.

He then demanded to see a tournament official before smashing his racquet during the opening game of the second set, an action that saw him cop a game penalty and drop his serve.

Sinner maintained the initiative from there, easing to a 7-6 (7-3) 6-3 win, with Kyrgios' mind clearly still focused on the performance of the official even after the dust had settled.

He posted on Twitter: "'You could do the job of the umpire' - what was said to my best friend that got me 'unsportsmanlike code violation' at 5-3 in the first set tie break.

"With 100 of thousands of dollars on the line that was the decision he made because the umpire's feelings got hurt. GET NEW PEOPLE"