Tristan Thompson Runs to Khloe Kardashian's Defense

Tristan Thompson is finally clearing the air about the circumstances under which he met Khloe Kardashian ... and he's also defending his other baby mama.

Tristan on Wednesday debunked a report he had reunited with his first baby mama, Jordan Craig. There were reports Tristan, Jordan and their 2-year-old son, Prince, recently went on family vacay in Jamaica ... making it seem as if they were rekindling an old flame.

Tristan says there's ZERO truth to that ... and adds he's spent the last few months preparing for the NBA season, and that's it -- zero summer vacations. As for how the story took off ... seems Tristan posting a picture of Prince on a yacht in Jamaica made some people think he was there, but he's adamant he was not.

Then there's this ... in a second tweet, Tristan played a little belated defense, adamantly saying he met Khloe when he was single. As we reported ... there have been longtime allegations she cheated with Tristan at the expense of Jordan.

At the time, Khloe's story was Tristan pleading with her that his relationship with Jordan was over long before they met. He's backing that up now, insisting he was absolutely a free agent.