TORRANCE, Calif. -- When you've accomplished everything Dan Henderson has in his combat sports career, it's tough to have many regrets.

The 46-year-old Southern Californian has traveled the globe earning accolades, from an amateur wrestling career that took him to the Olympics, to a UFC 17 tournament victory, to holding the 183- and 205-pound championships in Japan's PRIDE promotion, making him to date the only fighter to hold simultaneous major world titles.

But as Henderson prepares for one improbable final crack at gold at UFC 204 next month when he meets middleweight champion Michael Bisping, there's still one fight which he regards as the one that got away: Jon Jones.

"There's only one that really, Jon Jones, you know?" Henderson said. "I trained to fight him, got ready to fight him, got hurt and I didn't get a chance to test myself against him, you know? That would have been a fun moment to see how I do against Jon Jones. He's since then done even better. He's screwed up a little, too, but he's still arguably the best pound for pound guy out there."

Henderson was scheduled to challenge Jones for the light heavyweight title in the main event of UFC 151, but he suffered a knee injury in training. This led to one of the most infamous chains of events in the sport's history, as the UFC canceled the card, the first outright card cancellation in Zuffa history, and relations were strained between the company and Jones after UFC president Dana White tried to pin the blame on Jones.

While Henderson regrets never getting the chance to tangle with Jones, he's also realistic about where he stands now. Let's put it this way: There's a reason he's fighting middleweights now and not light heavyweights.

"Over the years, it's gotten harder to keep my body in the shape I need to," Henderson said. "That's why I dropped back down to middleweight, because it's harder to go against the heavier guys. Having DC's fat ass on top of me really didn't help. When he was on top of me, I decided to go down to another weight class."