The pair were seen partying in Miami after Kim, Tristan and her son Saint, 7, attended Lionel Messi's soccer match. The reality TV star and the NBA player went to celebrity hotspot Gekko to grab dinner post-game.
The duo then went to LIV nightclub together, where they partied "late into the night" alongside DJ Khaled. They were also joined by David Grutman and his wife, Isabela Rangel, per Tristan's Instagram Story.
The brunette beauty wore an all-black leather fit with tight pants and a high-neck cropped tank. Meanwhile, the basketball star sported a sheer black button-down, a chunky diamond necklace and black satin pants.
In response to the unexpected outing, fans bashed the mother-of-four for being so friendly with the Lakers athlete.
"Messy messy! I wouldn't even be speaking to this clown if it was my sister," one Twitter user penned, referencing the multiple times Tristan was caught cheating on Kim's sister Khloé.
"I think she's messing around with a basketball player, and Tristan is just the scapegoat," another fan theorized.
"Is she banging her sister's baby daddy?" a third person asked, while a fourth said, "They both sleep with everyone …so why not."
"Please let this not be what I have been thinking. She was his hardest critic when Dirty D cheated on her sister," a fifth user added.
As OK! previously reported, while Tristan has done Khloé dirty in the past, she is seemingly over it as she claimed she feels "bad" for the Lakers player and her other ex Lamar Odom despite their wrongdoings.
"Every single day, I feel bad about Lamar. Every single day, I feel bad about Tristan not being on a team right now," the Good American co-founder said on the Thursday, July 6, episode of The Kardashians.
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