Every MMA fan knows just how seriously Dana White takes the pound-for-pound debate.
The Brazilian KO artist had picked up 33 consecutive wins since falling short in his MMA debut in 2005.
In Domnick Cruz's injury-induced absence, Barao won the interim UFC bantamweight title and defended it twice before being elevated to the division's proper champion.
'The Baron' retained the belt with an epic first-round KO win over Urijah Faber at UFC 169 in February 2014.
That was enough to convince White the new pound-for-pound number one was a 135lb fighter.
"Look at the numbers and look at Renan Barao's fights, he's all there. He's the kind of guy that I like to watch. He's a killer, he comes in and he tries to finish you," the MMA mogul said before Barao's second title defense at UFC 173.
"Look at the efficiency of the kid, and how he has not been anywhere near being beaten in all those years. This is a sport where there's always a guy who may have better wrestling, better striking, or better something.
"I've been debating if he is No 1 pound-for-pound and, for me, he is."
Just days later, Barao got battered for five rounds as Dillashaw pulled off a late TKO victory in Las Vegas.
Barao earned a second crack at Dillashaw with a submission win over Mitch Gagnon in December 2014.
However, he never got anywhere near the form that made him White's favorite fighter.
Dillashaw stopped him even quicker when they rematched for bantamweight gold in July 2015.
A move to featherweight backfired as Barao was easily outpointed by Jeremey Stephens. The 38-year-old outpointed Phillipe Nover to get back in the win column in September 2016 - but he hasn't recorded an MMA victory since then.
Barao lost five consecutive bouts before finally being cut by the UFC at the end of 2019. In 2022, he Simão Peixoto choked him out in an exhibition bout. A year later, Barao lost again in the pro ranks against Walter Zamora.
Overall, he's suffered nine defeats since falling short in his first fight with Dillashaw all those years ago.
Still, he's preparing to fight again in 2025 as GFL will host Barao vs Faber 3 at an event later this year.
Only time will tell if Barao will snap his long losing streak against a man he's already beaten twice.