McGregor swapped the Octagon for the boxing ring last August to take part in a lucrative bout with Floyd Mayweather Jr.
The UFC’s lightweight champion held his own against the legendary boxer for the early rounds of the much-maligned contest but ended up suffering a tenth-round TKO loss.
It’s understood McGregor’s unsuccessful boxing debut saw him pocket over £100m, the biggest purse of his combat sports career.
And Rutten reckons the only he’ll make that type money again is if he has another boxing match.
“If he’s a smart guy he should keep on boxing – that’s what I would do,” Rutten told TMZ Sports.
“I think Paulie Malignaggi should be a great fight. I think a fight against ‘Pacman’ (Manny Pacquiao) is a hard fight.
“But a Mayweather rematch, I would love to see it. I mean this guy goes ten rounds against the best boxer in the planet.”
McGregor, 21-3, hasn’t set foot inside the Octagon since defeating Eddie Alvarez at UFC 205, a card which saw him become the first fighter in the promotion’s history to hold two titles simultaneously.
According to UFC president Dana White, his first fight back in the promotion is expected to be a lightweight title unification bout against interim 155lbs champion Tony Ferguson.
“Nobody has talked about (Nate) Diaz,” White said during the UFC 216 post-fight press conference.
“Diaz has never been talked about. That’s internet bulls**t.
“Tony is the interim champion, Conor is the champion, it’s the fight that makes sense.
“It’s the fight that has to happen. It doesn’t make sense, it’s the fight that has to happen.”
