Everything you need to know about this weekend's big fight.
Floyd Mayweather Jr. and Juan Manuel Marquez pose after a news conference Wednesday in Las Vegas. (AP)
Former welterweight champion Floyd Mayweather Jr., who retired as boxing's mythical pound-for-pound titlist in 2007, is fighting current lightweight champion Juan Manuel Marquez at a catchweight of 144 pounds on Saturday at the MGM Grand in Las Vegas (9 p.m. ET, HBO PPV).
Since the 32-year-old Mayweather left the sport after an impressive 10th-round knockout of Ricky Hatton in December 2007, junior welterweight champion Manny Pacquiao has inherited the pound-for-pound mantle with a string of electric victories over Marquez, Oscar De La Hoya and Hatton. Since Mayweather never lost that title in the ring, he says it still belongs to him. The prospect of a Mayweather-Pacquiao megafight -- perhaps for early 2010 -- looms over Saturday's fight.
Marquez, the world's No. 2 pound-for-pound fighter according to The Ring magazine, has collected titles at featherweight, super featherweight and lightweight -- becoming the fourth Mexican boxer to earn titles in three different weight classes after Julio Cesar Chavez, Marco Antonio Barrera and Erik Morales. But the durable veteran is perhaps best known for two fights he didn't win: a draw and a split-decision loss in two thrilling fights with Pacquiao -- fights many observers think Marquez won.
Mayweather's decision to quit boxing may have been the least convincing retirement in sports history. No one was surprised when Floyd came back. But the decision to fight Marquez instead of Pacquiao took many observers by surprise.
When two champions from different weight classes enter the ring, the heavier man typically wins. Mayweather is bigger, stronger and faster -- a brilliant defensive mastermind who's never been in trouble in any fight. Many observers have dismissed Saturday's fight as a mismatch, looking ahead to a Pacquiao showdown. But Marquez is a crafty, shrewd counter-puncher capable of spoiling those plans.
Mayweather turned pro in October 1996 after a decorated amateur career that culminated with a bronze medal at the '96 Olympics. One of the great defensive technicians of all-time, "Pretty Boy" has collected titles at super featherweight, lightweight, junior welterweight, welterweight and junior middleweight, cementing his place among the 50 greatest fighters of all-time. Critics say Mayweather's defensive, risk-averse style makes for boring fights, but you can't argue with the results -- 39 wins in 39 paying fights -- and the record-breaking pay-per-view numbers for his fights.
Marquez spent most of his career in the shadows of Mexican stars like Barrera and Morales, but moved to the forefront with a decision over Barrera and the vicious two-fight series with Pacquiao. One of the sport's most talented analysts, blessed with the ability to make adjustments in the middle of fights, Marquez consolidated the lightweight championship with a ninth-round stoppage of Juan Diaz in February.
*Exact weights to be announced at official weigh-in Friday (5:30 p.m. ET, The 101 Network)
They're both counter-punchers, defensive specialists who attack the holes that open when an opponent throws punches. That could be a stylistic nightmare for anybody hoping for a traditional slugfest. But while Mayweather is content to sit back and wait it out, Marquez has become far more willing to mix it up in recent years. While it's helped boost his popularity and prestige, this hasty and direct engagement has also backfired on occasion -- like when he suffered three first-round knockdowns in the first Pacquiao fight.
Mayweather's success has always been rooted in his preternatural ring instincts and extraordinary hand and foot speed -- an air-tight defensive skill set capable of frustrating and demoralizing opponents over the long haul. The sharpness of those tools after nearly two years away from the sport is a major question.
The biggest obstacle for Marquez is the weight difference. Mayweather, who beat De La Hoya for an alphabet belt at 154 pounds in May 2007, is most comfortable at welterweight. But Marquez has never fought above the 135-pound lightweight limit. Many doubt he'll be able to carry his punch to the catch-weight of 144 pounds, though supporters insist Marquez can win on resiliency, intelligence and superior boxing skills.
Oddsmaker William Hill lists Mayweather as a 1-to-4 favorite. Marquez is an 11-to-4 underdog.
Following a cautious opening from both fighters, Marquez is the busier fighter and stakes a points lead in the the middle rounds -- but doesn't have the strength to hurt Mayweather, who outclasses opponent down the stretch with superior technical skills and that vicious right hand. Mayweather by close decision.
What They're Saying
"Marquez says hes goin after my ribs but theres no weakness in MONEY MAY. Only ribs he'll b diggin n2 will b at Outback after I take him down." -Mayweather, on his Twitter account @MAYWEATHERMANIA
"In my mind, Floyd Mayweather is the number one pound-for-pound fighter, and to be number one, you have to fight number one." -Marquez
"Do you know what great means? Great is Michael Jordan, Floyd Mayweather, Muhammad Ali, Roberto Duran and Sugar Ray Robinson." -Roger Mayweather, Floyd's father and trainer
"I am up here taking pictures from the stage, because I want to capture the moment when Juan Manuel Marquez dethrones the king. I couldn't do it, but I will tell you one thing--Marquez is ready. I want to freeze the moment of history in the making." -Oscar De La Hoya, President of Golden Boy Promotions
Among Juan Manuel Marquez's notable knockout victories over the past few years is this one, over SI writer Chris Mannix. (John Iacono/SI)