McGregor was originally scheduled to defend his featherweight title against Rafael dos Anjos, but an injury to dos Anjos forced a last-minute change. Diaz offered his services coming off a December victory over Michael Johnson.
It's been an unconventional road to UFC 196, but the main event promises to be one of the year's most fascinating because of the change in weight for McGregor.
|UFC 196 McGregor vs. Diaz Odds|
|Source: Odds Shark|
Key Storyline: The Weight Class
It's not unusual for fighters to switch between weight classes in their careers. Anderson Silva, at the height of his middleweight powers, jumped up to 205 pounds for matches with James Irvin and Forrest Griffin.
Usually, though, the jump is just one weight class, and there tends to be a long gap between matches so a smaller fighter can get more accustomed to moving around with the additional pounds.
Using Silva as an example again, he had four months between fights before taking on Irvin and Griffin. McGregor has fought at lightweight but has been competing at featherweight for his last 10 bouts dating back to February 2012.
This is McGregor's debut at welterweight, meaning he's carrying 25 extra pounds. Diaz has alternated between lightweight and welterweight, so the 170-pound limit won't have any impact on him.
It's a credit to McGregor's competitiveness that he took this fight—not that he's lacking any confidence, per MMAFighting.com's Ariel Helwani:
MMA fighter Chris Fields said in an interview with Raf Diallo of Newstalk 106-108 in Ireland he thinks the added weight will actually help McGregor: "If you think of it like this, it's like trying to run a car on very little fuel, especially for the last few weeks of camp and Conor would be the same when he fights at featherweight. You're almost just battling against the weight rather than getting ready for the fight."
UFC President Dana White told Sports Illustrated it was McGregor who pushed for the 170-pound weight limit: "I tell Conor, ‘[Diaz] can’t do 160 pounds, he wants to do 165 pounds. McGregor’s response: 'You tell him it’s 170.'”
Diaz had trouble making weight for his fight with Dos Anjos in December 2014, tipping the scales more than five pounds over the 155-pound limit. He did hit that mark against Johnson four months ago, so even with a short preparation time, the 30-year-old shouldn't have any problem staying around 170 pounds.
Diaz is naturally bigger than McGregor. He's three inches taller at 6'0" and has a two-inch reach advantage (76 versus 74), though his 38-inch legs are two inches shorter than the Notorious One's. McGregor's greatest asset is his willingness to aggressively attack anything that moves inside the Octagon.
That physical style will suit McGregor well in a heavier weight class against a bigger opponent than he's accustomed to seeing.
There's a fearlessness to McGregor that is hard to ignore. Many fighters in the past have expressed their reluctance to move up even one weight class for a potential marquee matchup that would generate huge money for them and UFC.
Diaz is a fighter who needs to be motivated to perform well. This is the biggest fight of his career, so if he can't come out ready to attack, he never will. He's also been an inconsistent UFC fighter, owning an 8-8 record in his last 16 bouts.
McGregor hasn't lost since 2010, three years before making his UFC debut. He's taken down some of the best fighters in the business, including Chad Mendes and Jose Aldo in his last two matches. Even at a new weight class, his winning streak will continue in impressive fashion.
McGregor wins via second-round TKO
Stats courtesy of UFC.com unless otherwise noted.