OTTAWA - No one will confuse it with the classic bouts between Muhammad Ali and Joe Frazier. But for what it lacked in the sweet science department, the so-called "Thrilla on the Hilla" charity boxing match between Liberal MP Justin Trudeau and Conservative senator Patrick Brazeau made up for in hype.

Trudeau, widely acknowledged by Parliament Hill pundits to be the underdog going into the fight, emerged the winner when the referee stopped the bout midway through the third round.

"It feels really good. I had a game plan that I was going to stick to," Trudeau told reporters after the bout.

"I knew he would come in heavy and hard right off the bat, but I also knew that I was going to be able to take anything he threw at me. And when he did, he emptied himself out, and I just kept going.

"I'll be absolutely honest: he hits really hard."

For weeks, Trudeau and Brazeau sparred on Twitter, with the brash young senator from Maniwaki, Que., trying to bait the eldest son of the late former prime minister Pierre Trudeau into shaving his head in the event of a knock-out, and taking shots over the Liberal MP's controversial quip about Quebec separation.

"March 31st, (at)justinpjtrudeau will meet someone he knows (the left) and what he fears most (my right)! U gonna separate then?" Brazeau tweeted.

"Are you ok, Pat? That's even more unintelligible than usual. Stick to your usual grunting and snarling... " Trudeau wrote in reply.

On Saturday night, they took the fight to each other in a different sort of political arena.

The crowd, which included Conservative Cabinet ministers Leona Aglukkaq, Rona Ambrose and James Moore, and MP Pierre Poilievre, cheered Brazeau when he walked to the ring to the strains of heavy-metal music, clad in a Tory-blue robe with white trim. Trudeau was heartily booed as he entered the ring in a Liberal-red robe to K'naan's hip-hop tune, "Wavin' Flag."

Brazeau came out swinging, landing shots to Trudeau's padded head guard early and often. The Liberal MP weathered the blows, using his reach and speed to his advantage. By the end of the first round, Brazeau looked like he was running out of steam.

The Liberal MP came out swinging in the second round, landing head and body blows and nailing Brazeau with a flurry of punches in the corner. Trudeau kept up the assault in the third round until the referee called the fight.

"In the beginning, he had the upper hand. He was swinging with everything and I was playing defensive to let him come, because I knew one thing: I knew I could take anything he threw at me and keep going," Trudeau said.

"What was it in my training that allowed me to do that? It wasn't my training. It's how I am. I take hits and I keep going. That's a lesson that Pat learned tonight and maybe a few other people learned tonight."

"He didn't get me down," Brazeau said after the fight, his nose bleeding. He also challenged Trudeau to a rematch.

Ask what hurt most, Brazeau responded "Oh, definitely the ego."

"You know, I'm a fighter and I'm a competitive guy. Obviously I like to trash talk," he said.

"But again, I fell short tonight. But I'm still glad that I trained for five months for this. You know, I came up short 30 seconds, so maybe I'll try to make it up next year."

Brazeau was the odd-on favourite to win. The heavily-tattooed, pony-tailed Algonquin stands a solid five-foot-10, weighs 183 pounds and, at 37 years old, is three years Trudeau's junior. He has a martial arts background and served in the military.

The Liberal MP from Montreal is three pounds lighter and four inches taller than Brazeau. He took up boxing in his early 20s, sparring on and off in the gym over the years.

The Trudeau-Brazeau bout was part of the Fight for the Cure event, organized to raise money for cancer research, a deeply personal cause for Brazeau, who lost his mother to cancer, and Trudeau, whose father had prostate cancer.

The sold-out event raised $230,000 for the Ottawa Regional Cancer Foundation.