In stopping (Raging) Al Iaquinta with the first D'arce choke from the bottom in UFC annals, the Saskatoon native wrecked his elbow.
"When I was squeezing on Al during that D'arce, I heard him gurgle and I thought that meant it was close. Unfortunately I think it meant he was unconscious. So I squeezed as hard as I could," Clarke recalled.
He didn't stop, even when his elbow popped. The fight was finally called when the referee saw Iaquinta was out.
Ten months later, Clarke is ready to return to the cage. The Edmonton-base fighter takes on Michel Chiesa, winner of Season 15 of "The Ultimate Fighter," on a televised card Saturday in Fairfax, Va.
The main event at the Patriot Center pits Chad (Money) Mendes, ranked No. 1 among featherweight contenders, against No. 4 Ricardo (The Bully) Lamas.
Clarke is no stranger to pain. He injured his knee seconds into his second UFC fight, tearing a patella tendon when he kept going. Knee surgery was required afterwards. He says years of training and fighting have affected his posture, with a buildup of scar tissue.
"It's not an easy sport on the body unfortunately," he said.
The Iaquinta submission, at UFC 173 last May in Las Vegas, earned Clarke a US$50,000 bonus for performance of the night. But he had to spend the next four months rehabbing his elbow.
After that, he took time to improve his game. "I went back and watched the fight and noticed things I could have done better."
Clarke (11-2) spent seven weeks preparing for Chiesa (11-2) in Glendale, Ariz., at the MMA Lab, home to former UFC lightweight champion Benson Henderson.
The 29-year-old has now posted back-to-back wins over John Maguire and Iaquinta after opening his UFC account with losses to John Cholish and Anton Kuivanen.
Clarke, who has an environmental science degree, says the victories feel good but have made for a different type of pressure off.
"With the Maguire fight the pressure was hey, if I don't win this, I don't have a job and my dream's over. That puts a lot of pressure on you. Luckily I have a good team of mentors and coaches that were able to steer me in the right direction.
"This fight, the pressure's obviously changed in that I'm fighting on the main card against another tough opponent. But the pressure will always be there and the pressure's always to win. But I feel confident going into this one ... and I think pressure can bring out the best in you."
Chiesa is almost a 4-1 favourite according to the bookies.
But Clarke was also an underdog against Iaquinta. He was knocked down early, via a punch behind the ear, and spent most of the first round on his back.
"(You) outclassed him everywhere," Iaquinta coach Ray Longo said after the first round.
Clarke ended up on his back again in the second after a scramble but took advantage as Iaquinta tried to pass his guard, latching on a D'arce choke from the bottom that left Iaquinta unconscious.
"That was one of my money moves during the training camp," said Clarke. "I was letting guys pass guard so I could catch that. It worked out quite well in the fight. Now I own a little piece of history with that move in that fight. It's kind of cool."
D'arce chokes usually come from on top or side control.
The Canadian celebrated the victory in the centre of the cage, down on one knee in the thinker's pose as officials tended to Iaquinta.
"Don't sleep on me," Clarke yelled at the camera seconds later. "I'm here, baby."
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