It may be his biggest risk - but it's still a small one.
He's making it a catchweight fight at 152 pounds which favours him over El Canelo. He's also got many years of experience behind him while still at his prime whilst Alvarez is only 22.
A quote from Mayweather about catchweight fights 'I never fight people at catchweights because I am the best so I always want my opponents to be fighting at their best weights'.
The fact that he is making this at catchweight shows that he wants to tilt the fight in his favour.
I think he'll be too good for Alvarez although it will be a good fight as Alvarez is a very good boxer.
If it was at 154 pounds it would be a closer call but I'd still go for Mayweather due to his ring craftsmanship.
Manny is several fights beyond his best and it's a shame that he's still carrying on. Alvarez would knock Manny out if they ever fought.