Polish world No. 2 Iga Swiatek has been given extra security after a spectator at the Miami Open verbally abused the five-time major champion during a practice session last weekend, the BBC reported on Wednesday.
The man shouted personal insults about Swiatek's family and had previously sent abusive online messages to her through social media.
"The Miami incident appears to be a direct transition from verbal aggression online to harassment in the real world," Swiatek's representatives said. "He was aggressive and taunting."
The BBC said Swiatek's team reported the incident and that tournament organizers and the WTA put extra security measures in place around the player, who is scheduled to face Philippine wildcard Alexandra Eala in the quarterfinals on Wednesday.
"Security is a top priority. We monitor the network to catch these types of issues," Swiatek's spokesperson said.
"Constructive criticism is one thing, and threats, hate speech or even disturbance during training is another - this cannot be condoned."
The WTA did not immediately respond to a request for comment on the matter by Reuters.
The incident happened a little over a month after a spectator was removed from the Dubai Championship and banned after causing 2021 U.S. Open champion Emma Raducanu distress by exhibiting "fixated behavior" towards the British player.
Information from Reuters was used in this report.
