There's a theory that Floyd Mayweather has one flaw, and Manny Pacquiao is the perfect guy to exploit it

As dominant as Floyd Mayweather Jr. has been over the better part of the last 20 years, there has always been a debate in the boxing world about whether he’s susceptible to southpaws.

While he’s the favourite over Manny Pacquiao on May 2, some are making the case that Pacquiao — the best southpaw of his generation — has some inherent advantages that could carry him to an upset.

Oscar De La Hoya has been in the ring with both Mayweather and Pacquiao. He went on Tim Kawakami’s podcast on Thursday to talk about the fight, and mentioned the flaw in Mayweather’s impregnable defence that could give Pacquiao an opening.

“I’ve preached this all along. The left hand is the Kryptonite for Mayweather. He just does not know how to block a jab. It’s just not part of his arsenal. It’s not a part of his defence, blocking that jab.

“What’s going to be interesting is that Pacquiao has a lot of leg movement. So if he can keep firing that left hand, doubling it up and moving inside, moving outside he can give Floyd some trouble and make him think up there. Because you have to make Mayweather think. You have to take him out of his comfort zone. If Mayweather gets comfortable, he can cruise and win a relatively easy fight for 12 rounds.”

Pacquiao’s trainer Freddie Roach said something similar in an interview with SI’s Greg Bishop. Roach explained that Mayweather’s patented defence — where he guards his body with his left arm, deflects punches with his left shoulder, and blocks/counters with his right hand — won’t be as dominant against Pacquiao because he’s a southpaw.

Here’s Mayweather’s shoulder-roll defence in action against a righty. Would it be as effective against a lefty?

In preparation for the fight, Pacquiao has been watching tape of Mayweather’s 2006 fight against Zab Judah.

Judah, a southpaw, gave Mayweather relative problems early in that fight and even had the lead after four rounds. Before Mayweather took control of the fight and eventually won, Judah landed a left hand or two through Mayweather’s defence:

Pacquiao is quick, unorthodox, and a southpaw. In 2009 he destroyed De La Hoya in a beating that an HBO analyst declared “Death by 1,000 left hands.”

If anyone can take what Judah did well against Mayweather to the next level, it’s Pacquiao, right?

Both fighters are keenly aware of this dynamic. While Pacquiao is studying Judah to see what he can learn, Mayweather went a step further. He actually hired Judah to be his sparring partner during his pre-fight training camp. Mayweather is famously calculating and tactically intelligent when he gets in the ring. He should be fully prepared for Pacquiao’s left on May 2, despite the borderline-impossible-to-believe claim that he hasn’t watched a single Pacquiao fight on tape.

It’s also worth noting that Mayweather has beaten every southpaw he has faced, along with the rest of his opponents.

Despite that, the Floyd-southpaws thing has always had legs.

In 2012 Bob Arum — the Top Rank boss who promotes Pacquiao and was Mayweather’s promoter between 1996 and 2007 — said Floyd turned down $US100 million to fight Pacquiao because he hates southpaws (via Deadspin):

“But Mayweather will not fight him. Now why am I saying that? I’m not saying it to be, I know the guy and I know what his problem is, Mayweather, because we had him for 10 and a half years and his problem was he hated, he never wanted to face a southpaw and a southpaw that can move and punch with his left hand makes Mayweather completely vulnerable. All you have to do was watch him in the (DeMarcus) Corley fight where he didn’t realise Corley was one when he made the fight. Corley shook him up and had him in trouble. Why? Because Mayweather is a sensational defensive fighter but that’s against an orthodox guy. If he goes against a southpaw he opens himself up. You saw that happen in the Cotto fight because Cotto is a right handed fighter but he’s really a southpaw that’s converted and Cotto hurt him because he doesn’t have a good defence to the left hand.”

On May 2, Mayweather will get the chance to disprove this theory and end a debate that has lingered for years.

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