Naomi Osaka has burst into tears during her straight-sets loss to Veronika Kudermetova after being heckled at Indian Wells.

Early in the first set, with Kudermetova serving at 1-0, a woman called out to Osaka, rattling the 24-year-old.

Clearly distracted, Osaka lost her next service game to fall 0-3 behind in the match before approaching umpire Paula Vieira Souza to ask if she could "borrow" her microphone to address the crowd.

Osaka then spoke to WTA match referee Clare Wood at the change of ends, wiping away tears as she did so.

After a short delay, during which Russian world number 24 Kudermetova kept loose on court, Osaka rose from her seat to cheers from the crowd.

Wood appeared to tell Vieira Souza to intervene if she heard any undue comments from the crowd.

Despite earning two break points in the fourth game, the former world number one went on to lose the first set 0-6.

She went on to lose the second, 4-6.

At the conclusion of the match, Osaka spoke to the crowd, breaking down in tears as she did so.

"I just want to say thank you," Osaka said.

"To be honest, I've [been] heckled before and it didn't really bother me but it's … like, heckled here …

"I've watched a video of Venus and Serena [Williams] getting heckled here — if you've never watched it, you should watch it — and I don't know why but it went into my head and got replayed a lot.

"I just wanted to say thank you and congratulations [to Kudermentova]."

Serena Williams was booed in the final of the 2001 Indian Wells competition after accusations from Elena Dementieva that Williams' father, Richard Williams, "manipulated" the draw.

Venus withdrew from the semi-final against her younger sister just minutes before it was due to begin due to a knee injury.

Serena beat Kim Clijsters in the final but was subject to booing throughout the final, as were Venus and Richard, who watched on from the stands.

The Williams family and many others were adamant the vitriol was racially motivated and Serena, who won two titles at Indian Wells, did not compete there for 14 years, only ending her boycott in 2015.

In a 2021 interview with actor Will Smith — who played Williams's father in biopic King Richard — Serena Williams said she was still deeply affected by the experience.

Osaka, now ranked 78 in the world, has outlined issues with mental health in the past, saying she has struggled since winning the US Open in 2018, during which booing was also a prominent feature during what was a volatile final in which Williams defaulted after calling umpire Carlos Ramos "a thief".

And Osaka missed last year's Indian Wells tournament after suffering a shock third-round US Open loss to eventual runner-up Leylah Fernandez.

Osaka was subject to intense scrutiny after saying she would not take questions from the press at the 2021 French Open, as the nature of news conferences put an undue burden on players' mental health.

She eventually withdrew from the tournament.