Miocic (14-2) required just 54 seconds to knock Arlovski out, handing the former UFC heavyweight champion his first loss since March 2013. The heavyweight bout co-headlined UFC 195 inside MGM Grand Garden Arena.
A short right hand to the chin badly wobbled Arlovski in the early goings. The 36-year-old didn't go down from the shot, but he backed up dazed with his arms outstretched defensively. Miocic didn't let him off the hook and dropped him with a right hand moments later.
After referee Herb Dean stepped in, Miocic, from Cleveland, ran immediately toward UFC president Dana White to demand a title shot. He has won five of his past six.
"I didn't know, man, Andrei is a tough dude," Miocic said of the fight. "Former champion on a roll. You don't know what's going to happen. It's MMA. We're in small gloves. S--- can happen."
It is Miocic's 10th knockout of his career. Prior to his professional MMA career, he was an accomplished amateur boxer and Division I wrestler. Arlovski, who trains out of Jackson-Wink in Albuquerque, New Mexico, suffered his eighth knockout loss.
Tumenov outpoints Larkin
Russian welterweight Albert Tumenov (17-2) limped out of the Octagon with a split decision (29-28, 29-28, 28-29) victory over Lorenz Larkin (16-5). The two landed an identical number of strikes in the bout. While Tumenov greatly varied his attack, the majority of strikes landed for Larkin targeted Tumenov's lead leg. Tumenov failed to check the kicks and struggled to put weight on the leg late in the fight, but nevertheless came away with the win. It is his fifth consecutive victory. Larkin sees a two-fight win streak snapped.
Ortega stays unbeaten with win over Brandao
Featherweight Brian Ortega (10-0) remains unbeaten as a pro, as he submitted Diego Brandao (20-11) with a triangle choke at 1:17 of the third round. Ortega spent the first two rounds losing a standup battle to Brandao. The undefeated Ortega looked to take the fight to the ground in the third and the finish was beautiful; he transitioned from a mounted guillotine into the triangle seamlessly. He is 2-0 overall in the UFC.
Trujillo finishes Sims in Round 1
Lightweight Abel Trujillo (13-7), out of Blackzilians in Boca Raton, Florida, submitted Tony Sims (12-4) via guillotine choke at 3:18 of the opening round. Sims, 30, was dictating the standup well in the first, but he elected to shoot on a takedown and left his neck open for Trujillo, who finished the choke with Sims outside of his guard. The win snaps a two-fight skid for Trujillo.
McDonald submits Kanehara in return
Coming off a two-year layoff, bantamweight Michael McDonald (17-3) scored a remarkable comeback win over Masanori Kanehara (25-13-5) via rear-naked choke at 2:09 of the second round. McDonald, who hadn't fought since December 2013 due to hand and wrist injuries, didn't look sharp out of the gate. Kanehara caught him in an arm-triangle choke in the second round, but McDonald exploded out of the position and quickly transitioned to Kanehara's back. The 24-year-old improved to 6-2 in the UFC with four finishes.
Poirier outpoints Duffy
Lightweight Dustin Poirier (19-4) moved to 3-0 since moving up from the featherweight division, out-pointing Joseph Duffy (14-2) via unanimous decision (30-26, 30-27, 30-27). Duffy bloodied Poirier's nose in the opening round and bothered him with body shots throughout, but Duffy struggled to defend Poirier's takedowns. Once Poirier had the fight down, he dominated Duffy with elbows. The fight was supposed to happen in October in Ireland, but Duffy withdrew due to injury.