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What to watch at UFC 73

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With two championship matches, a pivotal showdown featuring Tito Ortiz, and fighters with something to prove up and down the card, UFC 73: Stacked at Arco Arena in Sacramento has a lineup worthy of its title.

What should you keep an eye on when the octagon gate shuts on Saturday night? Here are eight items of interest:

1. Can Anderson Silva stop a takedown?

Middleweight champion Anderson Silva (18-4) has fearsome Muay Thai skills, strong jiu-jitsu, and one big hole in his game: takedown defense. At February's UFC 67, Travis Lutter was weakened from his failed attempts to make weight the day before the match, but still managed to take "The Spider" down and win the first round before Silva rallied with jiu-jitsu from the bottom to open up strikes and claim a victory in the second.

How will the champ fare against Aurora, Colo.'s Nate Marquardt (25-6-2)? The five-time King of Pancrase champion in Japan is a world-class wrestler and ground fighter, with 14 of his victories coming by way of submission.

Silva wants to keep the fight standing, Marquardt wants to take it to the ground. Whoever can impose his will is likely to walk out with the title.

2. How is Sean Sherk's shoulder?

Lightweight champion Sean Sherk (31-2-1) is the longest-reigning current champion in the UFC – and yet his title defense against Hermes Franca will be his first. Sherk went into his title-winning effort over Ken Florian on Oct. 14 with a bad right rotator cuff, then was put on the shelf after surgery.

The Minnesotan faces a hot Hermes Franca (18-5) Saturday night. Franca's specialty is Brazilian jiu-jitsu, but he's displayed a frenetic style that defies easy categorization. Franca has a knack for pulling out victories when the chips seem down: At UFC 62, he dropped the first two rounds to Jamie Varner before finishing his foe in a wild third; and his toe-to-toe slugfest with Spencer Fisher in January featured ups-and-downs from both fighters before Franca scored a TKO win.

Has Sherk's shoulder fully healed, and can he shake any octagon rust, having fought just once in the past 15 months? And will his methodical wrestling style be able to keep up with Franca's "Energizer bunny" approach?

3. Tito Ortiz-Rashad Evans, part 1

For those wondering why mixed martial arts has commandeered some of boxing's audience, look no further than this match. When was the last time boxing gave the fans a match that means so much to the careers of both contestants, and put it on a card that already features two title fights?

Ortiz (15-5) is coming off a loss in his highest-profile bout, a third-round TKO against Chuck Liddell at UFC 66. His only win of note since returning to UFC was a hotly contested split decision against Forrest Griffin 15 months ago.

"Ultimate Fighter 2" winner Rashad Evans (10-0) is looking to step up. It was once said the former Michigan State wrestler was a boring fighter who only could go with his mat game. That was before he beat Jason Lambert with a convincing TKO at UFC 63, then followed with a highlight-reel KO head kick in a victory over Sean Salmon in January.

Is Evans ready for the elite of the light heavyweight division? Is Ortiz still there? We'll find out Saturday night.

4. Ortiz-Evans, part 2: Tito's a Bad Boy

Ortiz never fails to make time for his fans and has never met a microphone he doesn't like. "The Huntington Beach Bad Boy's" relationship with his employer, however, is a different story. The former UFC light heavyweight champion and boss Dana White seemed the best of friends in 2006 as Ortiz helped pull the company gravy train and reportedly earned him in excess of $4 million.

But the two have resumed their war of words in 2007. Ortiz recently told Yahoo! Sports' Kevin Iole "… they want to hold me down so that when it comes to negotiation time, they can say, 'Look, nobody wants to watch you any more. Nobody wants to see you.'" White responded, "His whole career, he's stepped over a dollar to pick up a dime. I'm sick of him."

This match should play a large role in determining who gets the upper hand in the ongoing war of words.

5. Is America ready for Antonio Rodrigo Nogueira?

Former PRIDE heavyweight champion Antonio Rodrigo "Minotauro" Nogueira's 29-4-1 record includes victories over the likes of Josh Barnett, Mirko Cro Cop, and Dan Henderson.

Now the Brazilian Top Team member gets set for his UFC debut, as he faces Texan Heath Herring (27-12). These two aren't strangers: Nogueira has beaten Herring twice, with a unanimous decision in 2001 and a second-round submission three years later.

Noguiera figures to be right in the championship mix. Herring is 3-3 with a no-contest in his past seven fights and at least needs to put in a strong showing if he's going to have a real future in the UFC.

6. Go with the Flo

Where does Ken Florian (5-3) stand in the crowded lightweight division? The Boston-area Brazilian jiu-jitsu black belt shook off his loss to Sherk on Oct. 14 with a thorough win over Dokonjonosuke Mishima in April. If Florian wants to keep his name in the top contender mix with the likes of B.J. Penn, Joe Stevenson, and Spencer Fisher, he will need to take out Alvin Robinson (8-1), a BJJ brown belt who trains under Royce Gracie.

7. Bonnar's back

Stephan Bonnar (9-4) was suspended for steroid use after his loss to Griffin at UFC 62 last August. Now he's back. But which Bonnar will we see? The one who scored wins over James Irvin and Keith Jardine? Or the guy who then looked lackluster in losing to Evans and Griffin? Bonnar's future will likely be determined when he faces Mike Nickels (5-1), who UFC fans last saw choking out Wes Combs last summer.

8. Let's be Frank

New Jersey's Frank Edgar (6-0) made his splash in the MMA world at UFC 67, where he bested Tyson Griffin by unanimous decision in what many still consider the UFC's match of the year. Edgar, who wrestled for Clarion University at 141 pounds, then had to decide whether to stay in the UFC and fight 155 or go to World Extreme Cagefighting and drop down to 145.

With that matter settled, Edgar is back and ready to take on undefeated Toronto product Mark Boeck (4-0), a jiu-jitsu black belt originally trained by the Gracies. This is a non-PPV show opener, but if the fight lives up to expectations, don't be surprised if it ends up airing on tape delay if the main card runs short.

Fighter records courtesy Sherdog.com's Fight Finder.

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