B.J. Penn is fighting for the wrong reasons and will pay for it Saturday when the two welterweights meet on a televised UFC card at KeyArena.
Penn — a former lightweight and welterweight champion — is fighting for status or legacy, the young Canadian argued.
"I'm fighting to hurt him," MacDonald said. "Not fighting for someone's opinion."
The two men were a study in attitudes at a public workout in a downtown hotel ballroom.
A relaxed Penn posed for photos with fans and signed autographs before coming over to renew acquaintances with reporters.
"B.J. Penn still holds court," said the smiling Hawaiian, who has fought 21 times in the UFC.
"Look at this," he added as he pointed to the wall of media around him. "I've got everybody around me. I'm the centre of attention. And I'm having fun. I'm living the dream, I'm living it up."
Penn (16-8-2) offered reporters fist bumps and hugs.
MacDonald, meanwhile, looked at the media like they were bugs, hardly moving a facial muscle as he endured an eight-and-a-half-minute scrum.
"I'm just focused, that's all," he said.
"It's good," said coach Firas Zahabi. "A young man that age usually would have his head spinning with all the attention he's getting. He knows there is one thing to do and there's one thing on his mind. That gives me a lot of confidence."
The bookmakers agree, making the 23-year-old MacDonald almost a 3-1 favourite.
Penn is known as The Prodigy, for earning his black belt in Brazilian jiu-jitsu in just three years and becoming the first non-Brazilian to win the black-belt division of the World Jiu-Jitsu Championship.
But MacDonald (13-1) is also a prodigy of sorts. He took his first MMA class at 14, learning all aspects of the sport from the get-go rather than coming over from wrestling or another speciality.
MacDonald had his first pro fight at 16 — his parents had to sign a waiver to make it happen — and was the youngest fighter on the UFC books when he signed a contract at 20.
Now 4-1 in the UFC, he is the seventh-youngest fighter in the organization and Zahabi calls him "probably the hardest-hitting athlete pound-for-pound I've ever trained."
The two fighters are worlds apart.
Away from the cage, Penn is probably to be found in board shorts. MacDonald, who says he had one outfit growing up, is a bit of a clotheshorse.
Penn is a father, part of a close extended family in Hilo, Hawaii. A single-minded MacDonald left home in Kelowna, B.C., to train in Montreal.
Penn is playful. MacDonald is private.
Macdonald lives, eats and breathes mixed martial arts — "He puts in a tremendous amount of training and study," Zahabi says.
The young fighter has no regrets about that single focus.
"I'm living my life the way I want," he says.
Zahabi, for one, believes the sky's the limit.
"In the end, I think if Rory keeps on the track he's on, he'll become world champion," he said. "I believe that."
Been there, done that for Penn. But his innate talent has sometimes not been matched by his training regimen.
He has wondered openly about why his name does not come up when people talk of MMA legends.
"Now that they're not saying it, he's upset about it," said MacDonald. "Maybe he should have learned that it's fickle."
At 33, Penn is giving up 10 years to MacDonald. And the six-foot Canadian looks like a different species compared to the five-foot-nine Hawaiian.
On Saturday night, it may look like a Hobbit fighting a linebacker.
But Penn is game.
"Just two men going into the ring that night, and when we square off on the day of the weigh-in, he's going to know something's not right," he said in his most threatening comment of the day.
Penn has come out of retirement to meet MacDonald, who is seen by some as the heir apparent to current title-holder Georges St-Pierre. He asked the UFC to fight the Canadian, who quickly accepted the challenge.
"I don't know who told him that I'm 50," joked Penn.
Penn normally walks around at 165 pounds, between lightweight (155) and welterweight (170) but says he has put on eight pound of muscle for this fight. MacDonald walks around at 185 or heavier.
Some wonder why Penn would choose to return at the higher weight class — let alone pick such a welterweight stud.
"I'm almost 34 now," said Penn, "And I don't see the point of eating chicken salad and training for six hours off that.
"I always thought and I always knew if I prepared myself properly at 170 pounds, that I could do well at 170 pounds. I've never walked into a ring and had a guy just wipe me right out. It's never, ever happened. So if I do it properly, I really feel like I could be a force in the division."
Opponents have worn him down at 170 pounds, however.
St-Pierre, a training partner of MacDonald's, wore him out and then hammered him at UFC 94 until Penn's corner threw in the towel. Jon Fitch endured an early Penn attack and then had his way with him in the third round at UFC 127. And Nick Diaz sent him into retirement at UFC 137 in October 2011 with a 178-88 edge in significant strikes.
Penn is 1-3-1 since beating Diego Sanchez in December 2009, incidentally the last fight MacDonald says Penn looked impressive.
Penn said he walked away after that run, thinking "where's this going, what's the point?" But he decided to come back after training with top fighters who had come to Hilo to work with him.
The two were slated to fight at UFC 152 in Toronto in September but MacDonald was forced to pull out after suffering a 38-stitch cut over his eye in training. Penn says he has used the extra time to his advantage.
"You know what this is the most sparring I've ever done for a fight and I think this is probably the best-prepared that I'm going to be."
MacDonald doesn't see a legend, just a victim in front of him.
"He just has to show up Saturday night."
In the end, Penn doesn't much care what MacDonald says.
"Sticks and stones. Sticks and stones."