Telling detail in photo of Nick Kyrgios' girlfriend at Indian Wells

Nick Kyrgios' girlfriend, pictured here wearing a mic during his clash with Rafa Nadal at Indian Wells.
Nick Kyrgios' girlfriend was mic'd up during his clash with Rafa Nadal at Indian Wells. Image: Amazon Video/Getty

Tennis fans spotted a key detail in footage of Nick Kyrgios' girlfriend watching him play against Rafa Nadal at Indian Wells on Thursday.

Watching on from the stands as Kyrgios battled the 21-time grand slam champion, Costeen Hatzi could be seen wearing a microphone pack in her back pocket.

'NEW LOW': Aussie tennis legend lashes out over $4.2b 'disgrace'

'UPSET PEOPLE': Tennis star speaks on girlfriend's video furore

Fans took to social media to question why she would be wired up, with many believing it had something to do with a new tennis series being produced by Netflix.

Netflix is currently filming the new series - touted as the tennis version of the Formula One doco 'Drive to Survive'.

Producers and cameramen have been spotted at ATP and WTA events around the world recently, including at the Australian Open in January.

"The series will be the first sports program of its kind to provide an equal platform to the men's and women's competitors of the sport, in keeping with the equal stage they share throughout the year," Netflix said recently.

On Thursday, reporter Graham Ruthven tweeted: "Nick Kyrgios' girlfriend is mic'd up for the Netflix docu-series, right?

"She's wearing a wireless mic pack on her waist. Surely that's what that's about?"

Rafa Nadal survives huge scare from Nick Kyrgios

Nadal extended his unbeaten start in 2022 to 19 matches after surviving a second-set stumble to see off Kyrgios.

The 21-time grand slam champion prevailed 7-6 (0) 5-7 6-4 on Thursday in an extraordinary battle between the long-time rivals.

Kyrgios unravelled on a number of occasions against Nadal but somehow managed to claim the second set and send the match to a decider.

However it all came undone when Kyrgios was irked by the crowd and double faulted to hand Nadal the decisive break at 4-3.

Nick Kyrgios and Rafael Nadal, pictured here after their quarter-final clash at Indian Wells.
Nick Kyrgios and Rafael Nadal shakes hands after their quarter-final clash at Indian Wells. (Photo by Clive Brunskill/Getty Images)

"How many f***ing times are you going to let them do that," Kyrgios raged, referring to noisy fans delaying his serve.

"Look at the f***ing score. Look at the score."

Kyrgios handed Nadal the first set when he was hit with a point penalty for an audible obscenity at 0-6 in the tie-breaker.

He had earlier received a code violation for smashing his racquet.

Nadal's hopes of winning a fourth Indian Wells title are still alive after he improved his record to 19-0 in 2022.

Only Novak Djokovic has won more matches to start a season before losing, going 26-0 in 2020 and 41-0 in 2011.

Roger Federer's best mark is 17-0 in 2018, while Djokovic also went 17-0 to start 2013, as did Pete Sampras in 1997.

Click here to sign up to our newsletter for all the latest and breaking stories from Australia and around the world.