Emelianenko (37-5) dropped Mir with a short left uppercut, then quickly finished him with strikes on the ground. The heavyweight fight, which would have been one of the biggest in MMA history had it taken place during their respective primes, headlined Bellator 198 in Rosemont, Illinois.
A former UFC champion, Mir (18-12) appeared to hurt Emelianenko with a right hand to the temple early. The Russian heavyweight quickly recovered from the punch, however, and even scored a hard takedown moments later.
After getting back to his feet, Mir aggressively went after Emelianenko with boxing combinations. Emelianenko, a legend of Pride Fighting Championship, calmly slipped Mir's strikes, before landing the stiff left hand that dropped Mir.
"I feel great joy and happiness," Emelianenko said through a translator. "Thank God we won."
It was the third bout of the opening round in Bellator's World Heavyweight Grand Prix. Emelianenko will advance to a semifinal matchup against longtime middleweight Chael Sonnen, who defeated Quinton "Rampage" Jackson in January. Bellator officials have not yet announced a date for the semifinals.
Saturday was arguably the most anticipated matchup of the opening round. Emelianenko and Mir were champions in their respective promotions in 2004 and are considered two of the best heavyweights of all time. The UFC pursued Emelianenko throughout his iconic career but was never able to secure a deal to get him to the Octagon.
When Mir, 38, left the UFC in mid-2017, Bellator president Scott Coker jumped at the opportunity to book the long-awaited matchup with Emelianenko.
For Mir, of Las Vegas, it was his first appearance since March 2016. He served a two-year suspension for a failed drug test in 2016.
Emelianenko, 41, signed with Bellator last year. He suffered a TKO loss to Matt Mitrione in his promotional debut in June. There is a chance he'll have an opportunity to avenge that loss in the Grand Prix finals. Mitrione is on the other side of the bracket and will face the winner of next month's Bader-Lawal matchup.
McGregor teammate Danis submits Walker in debut
Danis, 24, already has made a name for himself in MMA, despite zero pro fights coming into this weekend. He is a close friend and teammate of UFC star Conor McGregor and employs a similar style of self-promotion. Before Bellator 198, Danis claimed he already was the highest-paid fighter on its roster and said he would "own" the promotion in short order.
The New York native took a decent left hand to the head in the opening moments but eventually pulled guard on Walker and moved quickly into a submission. It's the third loss by submission of Walker's career.
"I said this before I came in -- no one has ever experienced submissions like this in MMA," Danis said. "I'm too good. This is another level.
"That leg lock, that's just jiu-jitsu. I'll give you guys a free seminar on how to defeat MMA with jiu-jitsu."
Immediately after the result, McGregor congratulated Danis on the victory via Instagram.
Danis trained for the bout in Dublin, at SBG Ireland. He has not formally retired from jiu-jitsu but has admitted he probably will need to do so as his MMA career takes off.
Sanchez pulls off arm-triangle, wins fourth in a row
Sanchez, 27, actually locked up the choke on the feet. He tied up Sicilia's arm in a standing position near the fence and put him to sleep shortly after they both toppled over to the canvas.
"It comes from the Muay Thai clinch," Sanchez said of the choke. "I wanted his legs, I wanted his back, I wanted everything. Sam is the real deal. I've been watching him for a long time. He's a killer. I was definitely prepared for this moment."
Fighting out of Roufusport in Milwaukee, Sanchez has won seven of his past eight. He has all but cemented a shot at defending champion Patricio Freire, having defeated Sicilia, Daniel Straus, Marcos Galvao and Georgi Karakhanyan. He has finished his past two opponents.
Nephew of Royce Gracie submits Torres
With Royce cheering him on cageside, Gracie took Torres down with an outside trip, moved to mount and then applied the choke. It is the seventh submission finish of his MMA career, and his first of 2018.
"I think the pressure was on Royce and Renzo [Gracie]; back then there was pressure," Neiman said of carrying the Gracie name. "We did what we're supposed to do already, so there is no pressure on me. I'm just having fun."
The New Yorker is now 6-0 in Bellator. Before Saturday, Torres, who is from Sonora, Mexico, had never lost by submission.
Lovato breezes through late replacement Harris
Middleweight Rafael Lovato Jr. (8-0) made quick work of late-replacement opponent Gerald Harris (25-6), submitting him via armbar just 1:11 into the first round.
It was an interesting matchup in that Harris, 38, considered himself retired as recently as this week. Harris agreed to take the fight on extremely short notice, when Lovato's original opponent, John Salter, withdrew because of injury.
Lovato, a 34-year-old from Oklahoma City, caught Harris in a triangle choke off his back, before switching to an armbar. It is the fifth submission win of Lovato's career and seventh finish overall.