The life and times of B.J. Penn

It’s a little early to get retrospective on the career of BJ Penn, but so far, it has all the makings of a great drama.

In Act I, we get the meteoric rise, as Penn blows through his first three opponents with an invincibility befitting a man dubbed “The Prodigy.”

Act II gives our hero his first glimpse of adversity, as he loses his first title shot to Jens Pulver, puts in two uninspired performances, and then earns an anti-climactic draw against Caol Uno in his second attempt at the lightweight belt.

Act III begins with Penn’s return to glory, scoring an upset win over Matt Hughes to capture the welterweight belt. But after a falling out with the UFC, he is forced to wander the Earth, taking fights where he can find them, sometimes three weight classes above his normal fighting weight.

Act IV sees Penn coming home to a hero’s welcome, but still falling short in his first two fights back in the UFC against Georges St. Pierre and Hughes.

Finally, Act V has our hero reborn as a lightweight terror, dominating his rematch against Pulver and then finally capturing the lightweight belt he has sought for so long in a blowout against Joe Stevenson.

It would be a wonderful story if it ended there. But the story continues this Saturday night as Penn faces Sean Sherk, arguably his toughest opponent yet at 155 pounds. FightMetric has tracked all of Penn’s 17 professional fights to get a historical perspective on how he might fare against a fighter like Sherk.

On his feet, Penn’s greatest advantage may not be something he does, but rather something he has. While his Hawaiian compatriot Wes "Cabbage" Correira may be better known for having an iron chin, the accolade is probably more fitting for Penn.

Cabbage has been knocked out, Penn has never even been knocked down. Perhaps his most impressive feat of sustained verticality was in his fight against Lyoto Machida. Penn moved up three weight classes for the fight. Saying nothing about Machida’s punching power (and his knockout of Rich Franklin would indicate he’s not just playing patty-cake), there was simple physics at play: Force equals mass times acceleration. A larger man (Machida weighed in at 218 pounds) can pack more of a wallop than a 155-pound fighter. In the second round of the fight, Machida connected with three devastating shots while Penn was pinned in the corner. Penn didn’t go down, he didn’t look rocked. What he did was connect with his own right hook and sent Machida backing up instead.

While many have pointed to Sherk’s cardio as a distinct advantage over Penn, it’s mainly because of an unfair characterization of Penn as someone who gasses easily. This rap is probably due to his performance in his last two fights at welterweight against St. Pierre and Hughes. In the St. Pierre fight, Penn dominated the first round only to slow down in rounds two and three and lose a split decision. Against Hughes, Penn owned the first two rounds but came out flat in round three and lost via TKO.

But this fight will be contested at lightweight, where Penn has fought two five-round fights before. Neither of those fights showed Penn to be any less effective in rounds four and five than he was in the earlier rounds. In fact, in his fight against Uno, Penn actually got stronger in the later rounds, fighting with greater effectiveness in rounds four and five than he did in rounds two and three. While Sherk will probably push the pace more than did Pulver or Uno, it’s not as if Penn has never fought for 25 minutes before.

One place where Sherk will hold a distinct advantage is in takedowns. Penn has fought a bevy of great wrestlers and his legendary flexibility has proved handy in avoiding takedowns. But eventually, these wrestlers always get Penn down. Opponents have attempted 67 takedowns against Penn, succeeding on 25 of them for a success rate of 37%. But that number is heavily influenced by two fights. Matt Serra succeeded on just one of 17 takedown attempts against Penn and Matt Hughes got just one of nine takedowns in their second match. If you remove these stats from the total, you have opponents landing 23 of 41 attempts for a success rate of 56%, which is even better than the average success rate of 48%.

Once taken down, and despite world-class jiu-jitsu, Penn doesn’t work for submissions or sweeps as do other Brazilian jiu-jitsu experts. Penn has only gotten one reversal in the 25 times he has been on his back and has only attempted two submissions from bottom position. Contrast that with a fighter like Frank Mir who averages one submission attempt for every instance in bottom position.

Where Penn’s jiu-jitsu really shines is when he’s on top. Penn displays extremely advanced guard passing. Penn has been in top position 27 times and has achieved 56 positional advances, an average of two times per instance. So every time Penn gets on top of his opponent, chances are he will end up in a position even better than half-guard. And his distribution of advanced passes is superlative too. A normal positional distribution for a very good grappler would look a lot like this one, belonging to Georges St. Pierre:

42% Half-Guard
25% Side Control
19% Mount
13% Back Control

It makes sense that the proportions decrease as the positions become more advanced, and harder to achieve. Here’s Penn’s distribution:

32% Half-Guard
20% Side Control
21% Mount
27% Back Control

Penn ends up taking his opponent’s back nearly as often as he gets to half-guard, a truly remarkable achievement. And while he has gotten a tapout every time he’s tried a rear-naked choke, he’s much more likely to use back-mount as an opportunity to throw strikes. In fact, Penn’s ground game can be characterized as one long flurry. Working at a frenetic pace, Penn rarely sits still, even if the only strikes he can land are small shots to the face and body. Using a favorite technique of covering his opponent’s mouth to disrupt his breathing, Penn works away, averaging 35 small ground strikes per fight. While those little “jabs” don’t cause a lot of damage on their own, they work extremely well in setting up the passes and big strikes that represent Penn’s best weapons and best chances to win the fight.

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