It’s official: Nick Diaz is finally stepping back into the UFC Octagon after more than six and a half years away. The 37-year-old American Diaz (26-9, two no contests) will return against “Ruthless” Robbie Lawler (28-15, one no contest) in a five-round fight which will serve as the UFC 266 co-main event on September 25. It’s a rematch more than 17 years in the making, after their classic first bout at UFC 47, where Diaz scored a second-round knockout against his 39-year-old compatriot with a counter-left hook. “I want to thank my team for getting s*** done,” Diaz tweeted after the fight was confirmed by ESPN, the UFC’s official broadcast partner, on Tuesday night. “It’s fight time. #KillorBeKilled #War.” ESPN reported that Diaz has already signed his bout agreement, but that Lawler has not yet signed his, though is expected to do so soon. TSN’s Aaron Bronsteter first reported the bout was in the works last week. No location has been confirmed for the pay-per-view event. Dana White was in a giving mood today when I asked him to tell me a random fight on the wall of the UFC War Room. Full Interview: https://t.co/1hBMXxtLVE pic.twitter.com/uQklZd9qTU — Aaron Bronsteter (@aaronbronsteter) July 8, 2021 Diaz has not fought since a January 2015 decision loss to former UFC middleweight champ Anderson Silva which was overturned to a no contest after both fighters failed drug tests, the Brazilian for a performance-enhancing steroid and Diaz for marijuana. A former WEC and Strikeforce welterweight champ, Diaz had three stints in the UFC before going on hiatus in 2015, having been hit with a five-year Usada suspension that was later reduced to 18 months. September’s UFC 266 card features two title fights, with The Ultimate Fighter coaches Alex Volkanovski and Brian Ortega settling their rivalry for the featherweight title, while women’s flyweight champ Valentina Shevchenko will defend against No 3-ranked Lauren Murphy.