Have the seeds been planted for potentially the next big crossover combat sports spectacle? Tristar Gym head coach Firas Zahabi hopes so.

Zahabi, the longtime coach of Georges St-Pierre, said today on the “JRE MMA Show” podcast that he’s been lobbying the former two-division UFC champion to chase a boxing match with Floyd Mayweather.

“I want Georges to fight Mayweather,” Zahabi told Joe Rogan. “I keep bothering Georges, ‘You fight Mayweather. You fight him.’ He’s like, ‘It’s crazy.’ I know it’s crazy.”

Is it, though? If there’s one thing Mayweather and former two-division UFC champ Conor McGregor proved, it’s that anything is possible. The two faced each other last August in “The Money Fight,” with Mayweather scoring a 10th-round TKO win.

The event proved to be a huge victory for both men outside of the ring, particularly for McGregor, whose estimated $100 million payday was by far the most he’s ever earned for a single fight. Mayweather vs. McGregor was good for 4.3 million pay-per-view buys in North America alone, second most behind Mayweather’s 2015 fight against Manny Pacquiao.

A venture into boxing would be a new for St-Pierre, who’s accomplished just about all there is to in MMA. He was UFC welterweight champ for more than six years from 2007-2013, a reign that included 12 title defenses. St-Pierre retired and returned four years later, defeating Michael Bisping by submission last November to claim the UFC middleweight title. St-Pierre hasn’t fought since but has expressed his desire to return.

Although the size discrepancy between St-Pierre (26-2 MMA, 20-2 UFC) and Mayweather (50-0 boxing) would seem to be an issue, Zahabi sees a way around that.

“They’ll fight at a catchweight,” Zahabi said. “Do you think Mayweather is worried that he’s going to be concussed? He’s fought all the top punchers in the world. He’s just going to have to worry about Georges’ volume and reach, but he can handle himself, and Georges can handle himself. But the whole world is going to tune into that one.”

St-Pierre vacated his 185-pound belt one month after winning it, revealing that he’d been dealing with ulcerative colitis, a chronic, inflammatory bowel disease. St-Pierre is looking to return to fighting but hasn’t mentioned boxing, only that legacy would play a big factor in deciding who he’d want to face.

McGregor and UFC lightweight champion Khabib Nurmagomedov have been mentioned as options for St-Pierre. But if it’s legacy that’s at the forefront of St-Pierre’s mind, and with nothing left to prove in MMA, taking a shot at Mayweather, who’s 50-0 and considered an all-time great in boxing, would meet that standard and then some.

According to Zahabi, there’s a particular reason why St-Pierre hasn’t brought it up.

“I’m like, ‘Georges do it,’ But Georges doesn’t want to fight a smaller guy, doesn’t want to call out a smaller guy,” Zahabi said. “So it’s going to have to come from Mayweather. It’s going to have to come from him.”

Mayweather retired from boxing (again) after his win over McGregor and has talked about fighting in MMA, though the idea has seemed to subside as of late.

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