Judo and Karate have more than white gis, colored belts and Japanese origins in common. Back in the mists of time, they also shared many common techniques, and still mirror each other's etiquette, terminology and philosophy. Gichin Funakoshi, Shotokan Karate's revered founder, adopted the white gi from Judo to give his new style legitimacy and respectability. Since then, both arts have evolved as two sides of the mixed martial arts coin, with Karate specialising in advanced striking, and Judo in grappling.

Watching these non-identical twins thus go their separate ways, like Luke and Leia Skywalker, makes it interesting to study the few core techniques they still have in common. Perhaps the most commonly used technique that is still core to both- and which would be a valuable addition to any mixed martial artist's arsenal- is the foot sweep, or as it is known in both arts, Ashi barai. Before looking at how valuable this under-used technique can be in MMA, let's see how it works.

Ashi barai is executed by holding the foot with the knife edge prominent (as if to execute a side kick), and slapping the side of the opponent's foot, ankle or lower leg in a way that sweeps it to the side, causing him to lose balance. This puts him at the untender mercy of the attacker's follow up strike or submission technique. In execution, think of it as using a broom or golf club to sweep in a sudden, arced motion. It is a remarkably efficient and versatile technique, achieving a complete takedown with precious little effort.

Here is Ashi barai being taught by a Karate Sensei:

And here is the Judo version being taught by a Judo Sensei (in Japanese, for extra authenticity):

Isn't that neat? To paraphrase an Internet meme, Two martial arts, One technique. This versatility is why Ashi barai could be such a valuable MMA technique in MMA. It can be used both as a strike from a distance (as it is used in Karate) and as a take-down from the clinch (as it is used in Judo). Let's look at it in practice in both martial arts.

Ashi Barai in Karate:

In Karate, the foot sweep is executed either from a distance (often being set up with a feint, but just as often being executed swiftly and without warning as a surprise attack to the foot, while the opponent expects a traditional punch or kick attack to the head or torso). It is also sometimes used after catching the opponent's kick, to violently sweep the other leg. Note that every single time a leg kick is executed in MMA, a foot sweep could also have been applied from the same position. And instead of just bruising the thigh, it would have resulted in an instant take-down. Here are some examples (see if you can spot Lyoto Machida):

De Ashi Barai in Judo:

For the Judo use case, we have one bountiful video that provides a sumptuous smorgasboard of dynamic foot sweeparation:

Ashi Barai in MMA:

The above videos show how Ashi barai can be used to effect a skillful take-down, and with amazingly little effort compared to other popular MMA take-downs like singles and doubles. It is also versatile in that it can be used from a striking distance (instead of a leg kick), in the clinch, or as an effective counter after catching a kick. Unfortunately, it is currently underused in MMA, probably because of the relatively small number of MMA fighters with Karate or Judo backgrounds.

For this reason, finding videos or gifs of ashi barai in the Octagon is harder than finding a virgin in Vegas. However, Jon Jones is a frequent exponent of the technique, most recently using it to take down Rashad Evans in their UFC 145 smackfest. Josh Thompson also employed it to great effect against Gil Melendez during their last rumble. Here are a few other examples I could forage from the web (thanks once again to Machida). Happy sweeping!