Lyoto Machida will put his undefeated record on the line against his ill-tempered and nasty compatriot, Thiago Silva -- who also has never tasted defeat -- in one of the featured bouts at UFC 94 “St. Pierre vs. Penn 2” this Saturday at the MGM Grand Garden Arena in Las Vegas.

What follows is a comprehensive look at the fighters, stakes and tactics of a bout certain to shake up the 205-pound rankings.

The Fighters

Machida possesses a unique life story for a modern-day mixed martial arts fighter. Coming from a strict traditional martial arts background -- he grew up as one of five sons to Yoshizo Machida, one of Brazil’s highest-ranked Shotokan karateka -- one might have expected his brand to have become obsolete in today’s quickly evolving sport. Think Teila Tuli, Art Jimmerson and Gerard Gordeau.

Machida not only stuck with traditional karate, but he continued his martial arts education and took up sumo wrestling and Brazilian jiu-jitsu. Living for years in the Amazonas area, he had the opportunity to train with some of BJJ’s best, like Fredson Paixao and Ronaldo Souza.

Through all the knowledge he has accumulated, the 30-year-old Machida – who’s half Japanese and half Brazilian -- has become one of the most complete fighters in the game. Unfortunately, he rarely uses those skills to entertain crowds, as he almost always puts effectiveness before aesthetics in his fights.

As a result, fans around the world who’ve had the dubious pleasure of watching Machida fight must feel, at times, like dieting monks in Cockaigne. Here you have a guy with incredible reflexes who effortlessly strings together spectacular combinations of kicks and punches, and, yet, he holds them back for most of the time to wait for a well-timed counter attack.

Machida’s defensive tactics have many experts under the impression that he’s too cerebral to finish off shaky opponents, and even though he can mix it up if he has to, it almost appears as if he dislikes the physicality of the sport. The UFC wants to sell that as an “elusive and highly technical style,” but in the boxing world, they might view him as a fighter who first of all makes his opponent look bad.

Machida’s opponent on Jan. 31 is almost his polar opposite. Even though the 26-year-old Silva comes from a martial arts background still considered “boring” by viewers who only tune into MMA occasionally -- like Machida he’s a BJJ black belt -- he understands the need to deliver spectacular fights and finishes. As a result, he adopted an aggressive stand-up style.

In four appearances inside the Octagon, Silva has made so little use of his excellent ground game that casual onlookers might mistake him for a pure striker. In reality, he’s a student of Jorge “Macaco” Patino, one of the most underrated BJJ teachers in the game, especially when it comes to grappling without the Gi, a vital skill for MMA.

Silva knocked himself through local competition in São Paulo, Brazil, by letting his heavy hands do the talking. Less than a year into his career, word reached Curitiba 250 miles to the south that Macaco had a genuine talent on his hands, and Patino formed a partnership between his Gold Team and the Chute Boxe Academy. That gave Silva the opportunity to train with Wanderlei Silva and Mauricio “Shogun” Rua, at the time considered to be two of the world’s premier 205-pound fighters.

Learning muay Thai from Rafael Cordeiro, one of the best coaches in Brazil, added another dimension to the young fighter’s repertoire. However Chute Boxe was not his final stop, as he linked up with Team Link in Ohio for his first three UFC fights before eventually joining American Top Team last February.

Much of the criticism directed at Silva has centered on the fact that he has yet to fight anyone of Machida’s caliber in his brief three-and-a-half-year career. Still, fighters like Dave Dalgliesh, Vitor Vianna and Tomasz Drwal are experienced and respected opponents, as everyone following the sport closely knows.