The UFC returns to pay-per-view for the eighth time this year on Saturday night as “UFC 163: Aldo vs. Korean Zombie” goes down at HSBC Arena in Rio de Janeiro.

There have been several injury-ridden cards in 2013, but UFC 163 takes the cake. The original main event, as well as several main- and preliminary-card bouts, were changed in the weeks leading up to the event.

Fortunately, the UFC’s lone undisputed Brazilian champion made it through training camp in one piece. Featherweight kingpin Jose Aldo (22-1 MMA, 4-0 UFC) looks to extend his remarkable winning streak to 13-0 since joining the Zuffa ranks in 2008 when he puts his belt on the line for a fifth time in the UFC, this time against Chan Sung Jung (13-3 MMA, 3-0 UFC).

That’s not all UFC 163 has to offer, though.

In the co-main event, two of the world’s top light heavyweight contenders collide when Lyoto Machida (19-3 MMA, 11-3 UFC) returns to his home country to face Phil Davis (11-1 MMA, 7-1 UFC).

Both fighters only have suffered defeats to men who currently hold or once held the UFC’s 205-pound strap, and one of them will attempt to make a distinctive case as the No. 1 contender with an impressive win.

With the event quickly approaching and lots on the line for all 24 fighters, let’s take a few minutes (with thanks to the UFC and FightMetric) to review some event-related facts about UFC 163.

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JOSE ALDO, UFC featherweight champion

Aldo has scored the most knockdowns in UFC/WEC featherweight history (seven). He also has never been knocked down himself in his UFC/WEC career. Aldo has successfully defended 61 of 66 takedown attempts (92.4 percent) in his UFC/WEC career, which is the best takedown defense percentage in UFC/WEC featherweight history. Among UFC/WEC fighters with at least five fights and 20 opponent attempts, Aldo’s takedown defense percentage is third all time behind Renan Barao and Gleison Tibau . Aldo has landed 106 of 124 leg kick attempts (85.5 percent) in his UFC/WEC career, which equals the sixth highest accuracy rate all time among fighters with more than 100 leg-kick attempts.

CHAN SUNG JUNG, top featherweight contender

Jung is the first South Korean fighter in UFC history to compete for a championship. With a win, “The Korean Zombie” can become the first Asian-born fighter in UFC history to win a world title. Previous Asian title challengers are 0-5-1. Jung is one of only three featherweights in UFC/WEC history to win “Knockout of the Night,” “Submission of the Night,” and “Fight of the Night” honors. The others are former WEC champs Urijah Faber and Mike Brown

LYOTO MACHIDA, light heavyweight contender

Machida returns to his home country to compete for the first time since April 2006. “The Dragon” has only fought two of his 22 professional fights in Brazil. With nine minutes and 30 seconds of fighting, Machida will pass Stephan Bonnar and Forrest Griffin for the third most total fight time for a light heavyweight in UFC history. Machida’s 82.3 percent takedown defense average is the best in UFC light heavyweight history (with a minimum of five fights and 20 opponent attempts). His opponent, Phil Davis, has completed at least one takedown against seven of the eight opponents he has faced in his UFC career. Machida’s 11 knockdowns landed are the second most in light-heavyweight history behind Chuck Liddell (14) and tied for fourth in UFC history.

PHIL DAVIS, light heavyweight contender

Davis will look to become just the second American, after Nik Lentz , to win two UFC fights in Brazil. “Mr. Wonderful” currently is the only fighter in UFC history to submit a Brazilian fighter in his home country. Davis owns a significant strike defense percentage of 74.2 percent, the best in light-heavyweight history and fourth best all time. The 28-year-old has yet to be knocked down in his 13-fight career.

MAIN CARD

PRELIMINARY CARD

The 14 preliminary-card fighters have a combined UFC record of 9-16-1. Of a combined 23 professional victories, Vinny Magalhaes and Anthony Perosh have won all 23 fights by knockout or submission. Neither man has ever won an MMA fight by decision. Anthony Perosh, 41, is the second oldest fighter on the UFC roster behind Dan Henderson Ian McCall is one of two fighters in the Top 10 of the latest USA TODAY Sports/MMAjunkie.com MMA rankings with at least two UFC fights and no victories in the organization. Lightweight Pat Healy is the other. McCall is ranked No. 4 at flyweight while Healy is the current No. 9 lightweight. Rani Yahya is just one of two fighters in UFC history to earn a north-south-choke submission. The other is Jeff Monson . Yahya has two such submissions in his UFC/WEC career. Yahya has earned 15 of his 18 professional wins by submission, with 12 in the first round. Yahya will compete in his home country Brazil for the first time since October 2004 – a span of nearly nine years. Josh Clopton returns to competition after a 609-day layoff. The 32-year-old has not registered an official MMA win since Nov. 28, 2009.

For more on UFC 163, stay tuned to the UFC Rumors section of the site.

(Pictured: Jose Aldo)