During the course of the week, I had been working on an essay about the finer points of infighting, in which I labelled it almost a lost art in boxing. It was for this reason that Josh Barnett's destruction of Frank Mir on the inside impressed me so much.

Through four minutes of grip changes, jamming his head into Mir's face to create space, and brutal strikes up and down the body, Barnett forced Mir to wilt under fire.

I have said it before and I will say it again, Josh Barnett's career focus has always been a little off.

His love of pro wrestling and fighting for underdog promotions has kept him out of the spotlight for far too long, and even though many have considered him a top heavyweight for a long time he has wasted a large number of fights meeting friends or people who should never have been fighting him anyway.

The light heavyweight Hidehiko Yoshida, a well past his best Jeff Monson, Gilbert Yvel, Mighty Mo: these are wasted fights and wasted potential.

Even when Barnett tried to meet better fighters as he joined Strikeforce's impeccable line up for the heavyweight grand prix, he still ended up missing out on elite competition.

In the course of that ill fated grand prix, Barnett met the two most one dimensional fighters in the tournament; Brett Rogers and Sergei Kharitanov. Both men fared about as well as you would expect against Barnett, getting submitted the same way with the same ease.

Barnett finally met Daniel Cormier in May 2012, a full six years after the last truly skilled heavyweight on his record, Antonio Rodrigo Nogueira and was soundly drubbed.

Coming into his bout with Frank Mir then, Barnett had a lot to prove.

Mir has made a name in recent years by beating legends on the back end of their careers, and if Barnett had lost a step since his days just below PRIDE's heavyweight trinity, it seemed like Mir would have another finish on his record.

Of course, fights are not affected in any way by rankings or expectations.

Barnett came in and manhandled Frank Mir in exactly the same area which Barnett's old foe, Daniel Cormier had just months earlier. The difference is that Barnett finished Mir within 5 minutes.

Barnett's assault was so varied and ferocious that it would be almost impossible to break it down movement to movement without writing a much, much longer article but there were plenty of key concepts on display from both men.

The first thing to notice is that as soon as the two moved into infighting or clinch fighting range, Barnett stayed tight while Mir began swinging both hands at once, his elbows coming far clear of his body. This is very important because while the commentary team and the crowd were impressed by Mir's punches, they opened Mir up for grips behind his neck and for underhooks.

While Barnett looked to be getting hit more cleanly as he moved Mir to the fence, he did get Mir to the fence and that is where Mir stopped being effective altogether. I say it time and time again but the importance of ring craft is that no-one can generate decent power with their legs straight underneath them and their back to the fence.

Mir continued to swing wide even with his back to the fence and this opened up grips for Barnett or opportunities just to land with shorter strikes like elbows.

The importance of not punching wide in the clinch was amply demonstrated by Antonio Rodrigo Nogueira versus Fabricio Werdum. Nogueira, however, had dominant position with Wedum's back to the fence.

As Nogueira got over-eager to do damage he let his punching arm loop out and Werdum grabbed an underhook on that side, used it to steer himself off of the fence and initiated the fight finishing grappling exchange.

Barnett looked magnificent on the inside as he switched between underhooks and collar ties, left handed and right handed blows, knees to the body and punches to the ribs or head. I don't rate Barnett highly as a pure striker, but as a thinking fighter he is second to none in the heavyweight division.

Barnett's constant use of his head to keep Mir standing was also wonderful and he used it to employ the classic (and rarely seen) Jack Johnson uppercut. Far from a traditionally recognized technique, this is simply the name I have given to a variant of uppercut applied masterfully by the first black boxing heavyweight champion of the world, Jack Johnson.

Even though it is the shortest punch in the traditional boxing arsenal, the uppercut lacks power at almost chest to chest range, so Johnson, while wrestling with an opponent, would turn his hips all the way through to the other side and bring his uppercut up almost perpendicular to where it would normally arc.

Here's a gif of Tim Boetsch using this type of uppercut against Yushin Okami.

Barnett was able to connect a couple of extremely stiff Jack Johnson uppercuts on Mir as Barnett used his head to brace against Mir.

The bout ended off of a series of grip changes and hard shots which culminated in a cross face and underhook being used to bring Mir into line for a hard knee strike. Mir sagged and the fight was called off.

Barnett knows Mir. He trained Ian Freeman for Frank Mir over a decade ago.

Of course Mir isn't the same fighter, he can strike pretty well now and wrestle better than before, but he is still prone to wilting under pressure.

Mir pulls off a big submission or finish, or he gets ground down. Mir's style is not to come back while under fire. In his notable comeback against Nogueira, it was Nogueira's decision to jump a guillotine rather than pound Mir out which gave Mir the chance to come back.

Barnett masterfully avoided grappling with Mir and avoided striking out in the open where Mir might have had something of an edge. Instead Barnett got to the inside, made the fight ugly and put on the finest display of clinch boxing I have seen in quite some time.

Is he one of the best rounded heavyweights in the world?

No. But Josh Barnett can hang with most, and on top of some serious ground and pound and terrifying leg locks, Barnett now seems to have found a more impressive and damaging way to use his wrestling (though it may be a little less crowd pleasing than the multiple suplex).

Pick up Jack's eBooks Advanced Striking and Elementary Striking from his blog, Fights Gone By.

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