Any conversation about Floyd Mayweather's flaws as a boxer is going to be a short one. A fighter can't go undefeated for over a decade while fighting at the world-championship level if he isn't great.
And, in general, to reach the top of the pound-for-pound rankings requires an extremely well-rounded game. In most cases, you are going to have to do some nitpicking to locate flaws in fighters at that level.
For this list I have relied on The Ring pound-for-pound top 10. I don't entirely agree with their assessments myself, and I think as long as they are owned by a major promoter like Golden Boy, they have to forfeit their traditional nickname of "The Bible of Boxing."
But it's still one of the most recognizable rankings and far more accurate than anything put out by the various alphabet-soup organizations.
Carl Froch took the hard, grinding road to boxing stardom. Never a flashy athlete, over the years he has proven himself to be an intelligent technical boxer with outstanding conditioning, a solid chin and respectable power.
But he's hardly a flawless fighter. Against his toughest competition, Froch has had trouble with his balance and footwork. He generally fights very well backing up, but a quicker and more explosive athlete can exploit that and drive him backward.
In a heated exchange, Froch will often square up his entire stance and lunge to reach his opponent. Andre Ward tooled him in these circumstances, and the younger George Groves had great success finding space to land heavy punches on Froch at such moments.
Froch has an iron will and is the type of fighter who does well taking a shot to deliver his own. But when he sells out and offers an expanded target to an elite fighter, it sometimes costs him much more than he's able to regroup for the effort.
While I consider it ridiculous for The Ring to rate Saul Alvarez in the pound-for-pound top 10, I do consider "Canelo" a very good boxer who is still getting better. And there is no doubt, in terms of box office, he's one of the top stars in the sport.
Floyd Mayweather has thoroughly outclassed nearly everybody he's ever fought, including pound-for-pound stars and future Hall of Famers. But Alvarez struggled more than most, because Mayweather's vastly superior use of movement had the redhead far out of position all fight long.
Alvarez showed similar difficulty with movement against Austin Trout when they fought in April of last year. I thought Alvarez definitely deserved to win the fight, but it was very close, and Trout's movement almost completely negated Alvarez's normally fearsome body attack.
It's why I wouldn't pick Alvarez to beat Erislandy Lara, and think he'd have a surprising amount of trouble against Carlos Molina. Canelo is still young and seems to get better with every fight. But as of right now, slick movement gives him trouble.
After Guillermo Rigondeaux's sterling performance against Nonito Donaire last April, it's hard for me to say Rigo has a "glaring flaw" and keep a straight face. The two-time Olympic gold medalist from Cuba earned a one-sided unanimous decision over a fighter who was universally ranked in the pound-for-pound top five.
And it was just his 12th fight as a professional.
But that historic performance has been greeted by a shocking apathy from boxing fans and even HBO itself. I'm of the opinion that Rigondeaux's biggest "flaw" is coming along during an era when fight fans lack the knowledge and attention span to appreciate a defensive wizard.
It is true that most defensive fighters risk losing rounds to their more active opponents. But Rigo controls space so well that it is generally quite obvious that his opponents aren't landing a thing, and he counterpunches with enough authority to slow down their intensity.
Manny Pacquiao started out as an explosive southpaw puncher and developed into a well-rounded, pound-for-pound superstar under the guidance of Freddie Roach. His most devoted fans tend to wildly overrate Pac's all-time standing, but he is still a great fighter with little in the way of glaring flaws.
Any aggressive fighter is going to be somewhat vulnerable to counterpunchers, and Pacquiao has had his biggest problems against Juan Manuel Marquez. But Marquez's countering is in a league of its own. And even against JMM, Pacman's blazing speed and use of angles has often proved more effective.
I think Pacquiao's greatest flaw has ultimately been his susceptibility to outside distractions. Pacquiao holds a cultural place in his native Philippines that is nearly unprecedented among professional athletes. A member of the Congress, Pacquiao is involved on a daily basis with serious issues that most fighters would hardly be aware of.
It's a delicate balancing act, and he seems to stumble with it at times.
Juan Manuel Marquez was underrated and overlooked for years. But late in his career, he has begun to fully garner the respect that he deserves. A strong argument can be made for him as the second-greatest Mexican fighter ever, behind only Julio Cesar Chavez.
You don't reach the levels Marquez has without world-class athletic ability. But he is among the great technicians of his generation, and it is his craft that has made him elite.
His exquisite timing has consistently allowed him to disrupt quicker fighters with his own counters. His four fights against Pacquiao have merely provided the most vivid examples.
Against quicker counterpunchers like Mayweather, Timothy Bradley and Chris John, Marquez has struggled. I think he should have gotten the nod over Pacquiao in their second and third fights, but Pac's speed advantage made the fights too close to call them robberies.
Marquez has pushed past 40 now, and while his style has never relied on speed, in the welterweight division, speed is the norm.
So it's fair to wonder how much longer the future Hall of Famer can stay near the very top.
Sergio Martinez did not even start boxing until age 20, so the amount of success he has achieved in the sport is truly hard to believe. He's been one of the most dazzling boxing stars of the past decade.
But Martinez is now 40 and has had multiple surgeries in the past two years. He has always relied on an extremely athletic style to beat his world-class opponents, and at this point it seems unlikely to me that he still has the body to pull that style off.
Unless he breaks down in the ring against Miguel Cotto this spring, I think he'll win that fight with relative ease. But I also think his days as the king of the middleweight division and an elite pound-for-pound star are behind him.
As the case of Roy Jones has poignantly illustrated over the past decade, a fighter who relies on extreme advantages in athleticism can seem to grow old over night.
Even most casual fans know the answer to this one. In many ways, Wladimir Klitschko has compiled one of the most dominant resumes in the history of the heavyweight division.
But three times Klitschko has been knocked silly by what looked to be inferior opponents. It's been nearly a decade since the last time it happened, but the memory still lingers.
And it's hard not to believe that the memory has stayed fresh in Klitschko's own mind, prompting him to fight with his vexing and cautious style. His last fight against Alexander Povetkin was the perfect example.
At times during the fight, Klitschko connected with monster punches that rocked the Russian challenger. But the world champion was also willing to turn the fight into a nearly unwatchable clinchfest in order to protect his lead.
Timothy Bradley had the best year of his career in 2013. His gutsy performance surviving Ruslan Provodnikov in March showcased his tremendous heart, iron will and insane conditioning. His split-decision victory over Juan Manuel Marquez in October demonstrated that he belongs among the sport's top technical fighters.
But it's no secret that Bradley lacks finishing power. After surviving a harrowing two rounds against Provodnikov, he completely controlled most of the rest of the fight. But his inability to put the Russian away nearly cost him the fight when Provodnikov came back to drop him in Round 12.
Bradley is an incredibly strong fighter and throws quick, crisp combinations. He hits hard enough to force most opponents to respect him.
Still, only 12 of Bradley's 31 wins have come by knockout, and his only stoppage in the past seven years was against an over-the-hill Joel Casamayor. He's undefeated in his career and has to be viewed as an elite fighter.
But he lacks fight-changing power, and that's a tough card to be without when you compete at the elite level.
Andre Ward has never had a close fight in his professional career. Aside from a couple of fights in grade school, he never lost as an amateur either. Ward has beaten the best fighters at his weight in the world and made it look effortless.
If he has a flaw at all, it is his inability to finish fights. Since 2009, his only stoppage has come against a weight-drained Chad Dawson.
The fighters who have gone the distance with Ward in the past few years have all been world-class professionals, and Ward has been able to make them all look second class.
But if Ward ever loses a fight, I have a feeling it will be against a guy who has hung around with him long enough to land a big punch in the later rounds.
Floyd Mayweather's career stretches back to the last century. He turned professional in 1996, and in the nearly two decades since he has gone a perfect 45-0.
So it can sound a bit silly to talk about the man's "glaring flaws." He isn't a knockout artist, but he's won 26 fights by stoppage, and when he starts landing his lead right, his opponents give him space and respect.
Mayweather doesn't throw a lot of punches by welterweight standards, but he's extremely hard to hit. The difference between the number of punches he lands versus what his opponents land is as dominant as any fighter ever.
So when we talk about Mayweather's flaws, we're really talking about how he measures up against the other all-time greats.
In this regard, his glaring flaw becomes more obvious. It's his lack of quality opposition.
Even this flaw gets grossly overstated by fans who hate him. Mayweather has been fighting world champions for over a decade. For the most part, he's beat the best of his era.
But when measuring all-time greats against each other, nitpicking is fair game. It would have been interesting to see him against a younger Shane Mosley, against Paul Williams and against Manny Pacquiao circa 2010.
If those fights had happened, I still think we'd be looking at an undefeated Floyd Mayweather. But there would be far less room to criticize his resume against the other all-time greats.