The 23-year-old from Lethbridge, Alta., slipped out of the grasp of jiu jitsu master Dan Miller on the floor and then pounded the veteran before the referee stopped the bout 4:42 into the opening round at the packed Bell Centre on Saturday night.
"I was just keeping pressure on him, fighting fire with fire," said Mein, who suspected that the win on the undercard of Georges St-Pierre's title fight may have been easier than expected because 31-year-old Miller was battling a flu.
"I saw he was little sick after weigh-ins," he said. "Going to the body doesn't help that. That's what hurt him and that's what put him down."
Miller (14-7 with one no contest) took Mein down early but the younger fighter rolled over and managed to escape and get straight back up on his feet.
Then he dropped Miller with a left hook, waited a little, and knocked him down again with two left jabs and a right before finishing him with a flurry of punches on the floor.
It was the first time Miller was stopped before the limit in UFC.
"When I got out of that arm bar I got right up," said Mein. "He's a black belt in jiu jitsu and he's a dangerous guy on the ground. I knew not to mess with that."
Despite his youth, Mein is a mixed martial arts veteran who fought extensively in other organizations, including Strikeforce, before finally getting his chance in UFC. His overall MMA record is 27-8.
The lanky fighter who grew up in a fight family is felt to have potential to go far in UFC. He doesn't hide his ambitions. Mein said he keeps a list of every welterweight in UFC on a white board at home to remind of who he may meet one day in the octagon.
But he has no preference of who he faces next.
"You've got to have your goals set in mind," he said. "I look at that list every day.
"Dan Miller's name is there. But it's just a list."
It was a tougher night for local favourite Patrick (The Predator) Cote, who was fighting at welterweight for the first time after spending most of his career facing much bigger opponents as a middleweight.
Cote (20-8) was given a unanimous decision over UFC newcomer Bobby Voelker (24-9), even though he spent nearly the entire third and final round being pounded on the ground by the American.
A huge roar, as much in surprise as glee, erupted when it was announced that all three judges scored it 29-28 for Cote, a result that stunned Voelker's camp who were certain they had won.
"I was a little bit worried because I knew I was losing the third round, but in my head I knew I won the first, and the second was tight," the 33-year-old Cote said. "I wasn't 100 per cent confident but I gave everything I've got.
"The judges know MMA better now and they gave me points because I was working when I was on my back."
Cote scored with some good early shots, but was taken down midway trough the first and spent the rest of the round fighting off arm-bar attempts.
He landed a big uppercut in the second, but came out of the round bleeding heavily from above the right eye after being caught twice with knees.
The third round was all Voelker, who got an exhausted Cote down and pounded him.
"To be honest, I got tired in the third round," he said. "It's the process.
"I'm still learning about dropping weight this way. I felt good at the weight cut. It was one of the easiest of my career. But now I'll talk to my team, my nutritionist, and it's going to be better next time."