Serena Williams Teases Bulgarian Tennis Player Grigor Dimitrov Over Tracksuit: 'Is That Mine?'

Serena Williams is keeping a close eye on her fellow competitors — and their outfits — at this year’s Australian Open.

The professional tennis player, who will play in the third round of the tournament Thursday, couldn’t help but comment on one of her fellow athlete’s clothing choices on the court earlier this week.

Bulgaria’s Grigor Dimitrov turned heads as he entered the first round of the tournament Monday dressed in a navy tracksuit with yellow spots.

According to the ATP Tour, the Nike designed tracksuit was Dimitrov’s way of “being different” and “fun,” he told the outlet after he defeated Argentina’s Juan Ignacio Londero 4-6, 6-2, 6-0, 6-4. “I don’t want to be vanilla,” he added.

On the day of the match, Dimitrov shared a photo of his outfit to Instagram, which later sparked a hilarious comment from Williams.

“Ummmmm is that mine?” the 38-year-old athlete quipped.

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Williams wasn’t the only one to recognize Dimitrov’s standout outfit online.

One Twitter user compared the Bulgarian athlete to a spotted blowfish.

Another user wrote that his outfit “looks like a onesie!”

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Others praised the tennis player for his sense of style, calling it the “highlight of the Australian Open so far.”

Another fan shared, “Ok despite widespread criticism, i give @GrigorDimitrov’s 5/5 stars. I dont understand the hate.”

While Dimitrov is no longer in the competition, fans can continue to look out for additional fun athlete fashion choices as the tournament continues through February 2.