The middleweight championship fight will mark the first UFC bout Roach has ever cornered. If things go according to plan, it won't be the last.
Roach has known St-Pierre for years and actually helped negotiate his latest UFC contract. Starting last month, Roach flew from Los Angeles to Montreal on a weekly basis to be involved in St-Pierre's preparations for the fight.
At 57, and with several active boxers still under his wing, Roach admitted it was a demanding schedule -- but he's meshed well with St-Pierre's team at Tristar MMA and is committed to the final chapter of the Canadian's career, however long that lasts.
"I've never been an elite MMA trainer, but Georges made me promise I would work his corner and I'm holding up to that," Roach told ESPN.
"This might be a little different than boxing, but it is combat sports and I know how to fight. I used to be a wrestler in high school. I was never a great wrestler but I have an idea on it and watching it during camp has given me a better idea. Everyone in the corner is real friendly with one another and I will give the best information I can in there on fight night, and it won't be strictly boxing."
St-Pierre (25-2) has been a little coy on any plans that go beyond next weekend at Madison Square Garden. He's stated that, contractually, he must defend the UFC's middleweight title if he wins on Nov. 4 in New York.
The former welterweight champion has also said he'll walk away if he loses, and that either way, he's not interested in calling out a money fight with the sport's biggest star, Conor McGregor.
Roach has an inside track to St-Pierre's long-term plans, due to his role in contract negotiations. He declined to detail St-Pierre's ideal scenario, other than to say it currently involves three fights.
He admitted, personally, he'd welcome a fight against McGregor.
"McGregor is a cocky kid and he did OK in his fight against Floyd Mayweather. I would just say OK," Roach said. "I would enjoy that fight and I would like to see that fight happen. It's possible.
"Right now, we're just concentrated on this fight. The thing is, we have a three-fight contract with [UFC president Dana White] and we have to win every one for the contract to go on. If everything goes well and Georges wants to retire at the end, that's up to him. If he still has fight in him, and if I still have fight in me, we'll go on from there. I'm sure he'll receive many offers. Bigger and better offers."
Of course, defeating Bisping (30-7), a good boxer in his own right, must come first.
Roach said he's happy with the progress St-Pierre has made in his striking and believes he can win in that area, but the game plan won't shy away from St-Pierre's well-known ground game.
"Everyone is talking about Bisping's size, but I say, 'Hey, I love fighting big guys,'" Roach said. "Tall guys give you a bigger target obviously, and are a lot slower. I think this guy is made for us. He says he doesn't think we can outbox him. We can and we will outbox him.
"If a [standup fight] happens, then is happens. But the thing is, if we have other opportunities to do things Georges is more accustomed to doing, we will do that.
"Believe me, we're not going to be like Ronda Rousey, where someone told her she was a good boxer when she was winning every fight of her life on the ground. I'm not going to lie to my fighter. We've been working on everything and will take advantage of everything."