The pair meet for the Mexican's four 168lb world titles on September 30 in Las Vegas and with Charlo jumping up two weight divisions to face one of the world's best pound-for-pound fighters, many are billing him as the underdog in this contest. 

However, Shields believes that if Charlo can be on the front foot and dominate rounds against Alvarez, the 33-year-old has a strong chance of winning the contest. 

"Charlo is one of the few fighters who holds his power throughout the whole fight. You don’t get too many of those, but Canelo is also able to do that. It really makes this a great fight,” Shields told a roundtable of reporters.

“Charlo has to make sure he wins rounds convincingly. You won’t win close rounds against Canelo. You have to keep pushing. Canelo has great defense, so Charlo has to be in great shape and push from beginning to end.”

Shields also highlighted one area which Charlo should target if he is to have the best chance of beating Alvarez, but he did warn that it is easier said than done. 

"You don’t see a lot of fighters go to Canelo’s body, because it’s hard to get close enough to do it,” Shields continued.

“He’ll have to come up with a scheme to get into that position.”