Chiesa (14-3) was scheduled to face Anthony Pettis at UFC 223 at Barclays Center in Brooklyn, but was forced off the card when he suffered facial cuts from broken glass. On that same card, Khabib Nurmagomedov claimed the lightweight title over Al Iaquinta.
Had Chiesa been healthy, he believes the UFC would have come to him to challenge Nurmagomedov for the 155-pound title -- not Iaquinta. That title fight was shuffled at the last minute when Nurmagomedov's original opponent, Max Holloway, was pulled for medical reasons.
"I lost a title shot. I have proof," Chiesa said. "I was the highest-ranked guy on the card. I would have stepped in to fight Khabib at the drop of a dime. I've always loved the fight with Khabib.
"Bless his heart, he's a cool-ass guy, but this is a sport and I've always liked the way I match up against him. And I got f---ed out of that opportunity."
When asked if he is planning, or is in the process, of taking legal action against McGregor, Chiesa replied, "No comment on that."
The UFC eventually rebooked Chiesa's bout with Pettis for UFC 226, which will be held next weekend in Las Vegas. It is worth noting the UFC explored Pettis as a replacement for Holloway at UFC 223, but did not come to terms for various reasons.
Chiesa, who is originally from Washington but fights out of Las Vegas, referred to the incident as "heartbreaker."
"You work your whole life for those kinds of opportunities," Chiesa said. "Do I want mine on short order? No. I'd love a training camp. But if they walked in the door right now and said, 'Do you want to fight for the title in the next 10 minutes?' I'm out the door, warming up, ready to go.
"To lose that opportunity, man, that's tough, You know how this sport works. Opportunities like that don't come along. I could string together 15 wins in a row and still not get a title shot. I lost my opportunity and dream, and I'm going to fight my ass off to earn it back."
McGregor is still facing criminal charges for the incident, including a felony criminal mischief charge. He is in the process of negotiating a potential plea deal with the Brooklyn District Attorney's Office. His next court date is scheduled for July 26.
"I regret my actions that led to today," McGregor stated at a court appearance earlier this month. "I understand the seriousness of this matter and I am hopeful this will get worked out."
The UFC has not made any announcement on a potential promotional punishment on McGregor.