<p>As ever with boxings most storied ancestral rivalry, the atmosphere will be positively fevered and the stakes through the roof when Miguel Cotto climbs through the ropes on Saturday night to defend his lineal middleweight championship against Canelo Alvarez at the Mandalay Bay Events Center on the Las Vegas strip.</p> <p>Cricket has India v Pakistan and soccer has Brazil v Argentina. In the fight game, its Puerto Rico v Mexico, a long-running international feud that over time has realized the mad valor and savage beauty of this cruel trade more completely than any other.</p> <p>There have been nearly five dozen world championship bouts between fighters from these boxing-mad Latin American nations through the years, and theres every reason to expect Saturdays showdown between Cotto and Alvarez, two of the sports biggest attractions today, will rate favorably with past classics, taking a place among the rarified air of Salvador Sanchez v Wilfredo Gomez, Julio Cesar Chavez v Hector Camacho, Jose Luis Ramirez v Edwin Rosaro and Felix Trinidad v Fernando Vargas.</p> <p>Cotto (40-4, 33 KOs), who last year became the only Puerto Rican fighter to capture world titles in four weight classes, is coming off a <a href="http://www.theguardian.com/sport/2015/jun/06/miguel-cotto-destroys-daniel-geale-and-calls-for-superfight-with-canelo-alvarez">third-round TKO of Daniel Geale</a> in defense of the WBC middleweight title he won from Sergio Martinez. That victory also made him the lineal champion at 160lbs.</p> <p>Alvarez (45-1-1, 32 KOs) is fresh off a <a href="http://www.theguardian.com/sport/live/2015/may/09/canelo-alvarez-v-james-kirkland-live">three-round destruction of James Kirkland</a> in May. The red-headed son of a Guadalajara ice-cream vendor, whose lone career setback was a <a href="http://www.theguardian.com/sport/2013/sep/15/floyd-mayweather-beats-canelo-alvarez">points loss to Floyd Mayweather</a> in 2013 that did little to diminish his runaway stock, is a former junior middleweight champion with victories over Erislandy Lara, Austin Trout, Alfredo Angulo and Shane Mosley on his ledger.</p> <p>Cotto is 35, nearer to the end of a surefire Hall of Fame career than the start, but having enjoyed a latter-day resurgence since teaming with seven-times trainer of the year Freddie Roach. Canelo is 25, already a household name with a rock-star-like following in Mexico and on the doorstep of mainstream superstardom abroad.</p> <p>Its a fight hardly wanting for built-in storylines, one that has fortunately required little bombast from the principals themselves, both soft-spoken types whose preferred language is performance. The rarity of summit meetings like Saturdays between rival promoters top charges  Canelo has been groomed by Golden Boy, Cotto the marquee signing to Jay Zs nascent Roc Nation Sports  only heightens the sense of occasion.</p> <p>The stylistic matchup between two of this generations classiest boxer-punchers is as difficult to read as any major prizefight in recent memory. Cotto is about a 2-1 underdog, though a victory for the seasoned champion against the relatively untested challenger would hardly register as a major upset. </p> <p>What it means beyond Saturday night is even more enticing. The winner will face overwhelming public demand to meet Gennady Golovkin, who reasserted his status as the divisions alpha dog with a <a href="http://www.theguardian.com/sport/2015/oct/18/gennady-golovkin-stops-david-lemieux-in-eighth-to-unify-middleweight-titles">clinical beatdown of David Lemieux last month</a> at Madison Square Garden, adding the Canadian punchers IBF middleweight title to his WBA and WBC straps. A blockbuster clash between either Cotto or Canelo and the knockout artist known as Triple G to unify the belts at 160lbs would surely be 2016s biggest fight.</p> <p>But only after the matter of Saturdays hotly anticipated semi-final, a treat of a title bout with implications far beyond the ring, is settled.</p> <p>All I have to say is that I am ready, Cotto said at Wednesdays final press conference, scarcely above a whisper and typically to the point. I know that Canelo is ready too.</p>