LAS VEGAS - Today's round features some bulls who already have one out here, and some who haven't gone yet this week. There are some outstanding matchups in this round outside of the event leaders and World Championship contenders. We should see some big scores here today.

Event Leaders:

Robson Palermo on 530 Gray Squirrel:
Gray Squirrel is a great bull, but he is far from being rider-friendly. In his career he's been ridden six times in 71 outs. His numbers for overall difficulty are almost identical to another bull in this round - Charlie Bullware - who has long been known for his ability to put the top riders on the ground. Gray Squirrel has been ridden only by left-handed riders; he likes to go to the left, but he's no piece of cake. If Palermo could stay healthy, a lot of this drama about the World Championship would disappear because he would run away with it.

Luke Snyder on 708 Delco:
Snyder got on Delco in Thackerville, Okla., in 2011 and lasted 4.62 seconds. This is a bull who likes to go left, and has been ridden more often by left-handed riders. He sent Silvano Alves home with no score twice in the second half of this season.

Mike Lee on 620 Blonde Bomber:
This bull got the best of Caleb Sanderson last night, but that is unusual for him. Built Ford Tough Series riders are 6 for 9 on him.

Renato Nunes on TD2 Bucking Machine:
Nunes posted two 90-plus-point rides on this bull back in May of this year. Bucking Machine is really a good fit for Renato Nunes; he is a fast bull who spins to the left, and essentially gets guys off by never letting off the gas. Once a rider gets a split second behind, he can't catch back up. Nunes, however is far better than most riders at catching back up. Can Nunes ride a bull that spins 90 miles an hour to the left? You bet he can. This should be a great ride.

Edevaldo Ferreira on 669 Blue on Black:
This is a bull who is unridden in 12 career outs. He first appeared on the Built Ford Tough Series in San Antonio in August, where he tossed Chase Outlaw.  After that, he got the best of J.B. Mauney and Silvano Alves, before coming here and dismissing Ben Jones in Round 1.

Chris Shivers on 30S Monty The Bull:
Cody Nance was 88.5 points on this bull in Springfield, Mo. Monty's been a good bull for several years now. He's been ridden more often by left-handed riders, and Chris is one of the best left-handed riders in history.

Austin Meier on 601 Shepherd Hills Trapper:
Meier has been on this bull four times and has ridden him twice. Trapper has a corner that is basically unrideable. He may not do it every time, but he can have the lowest, quickest, nastiest corner in the business. Meier is the only guy who's earned a score on him when he's done it, and he tried it on Meier twice in one ride. This should be a good matchup.

Emilio Resende on 631 Tapout:
This bull was ridden twice in September for 86.75 points each time. He's been ridden five of 13 times on the Built Ford Tough Series.

Cody Nance on 415 Cool Spot:
Although Cool Spot is not as famous as Chicken on a Chain, he is retiring at this event too. In his career, which goes back to 2007, he's never been ridden by a left-handed rider. Nance has a tough task here, as Cool Spot is a bull with world-class difficulty.

Top 5 Riders:

Silvano Alves on 01B High Octane Hurricane:
Alves is the only man who has ridden this bull in the past year. He was 89.75 points on him in Albuquerque, N.M. Hurricane's overall record puts him in with the most difficult bulls in the PBR, and certainly among the most difficult in this round.

Valdiron de Oliveira on 857 Sue:
Oliveira had this bull here last year in Round 4 and was 86.75 points on him. He also earned an 84.5-point score on him in March of 2011. Sue is capable of producing bigger scores as well - Marco Eguchi had two rides of 90 and 89.25 on him early this season. Oliveira needs Alves to come down, and he needs a big score here to keep hope alive going into the short round.

L.J. Jenkins on 93 Plummer Butt:
Oliveira was 86 on this bull in Philadelphia. Overall, Plummer Butt has only been ridden four times in 23 career outs, and is 4-2 against Built Ford Tough Series riders.

Guilherme Marchi on 52 Blueberry Crush:
By the numbers, this bull is a lot like Jenkins' bull. He's 25-5 against everyone and 4-3 on the Built Ford Tough Series level. Way back in January, Justin Koon was 88.5 points on him.

.J.B Mauney on 164 Great White:
Ben Jones got a reride due to a foul on this bull in Round 3. He's only been ridden once in 21 career outs, and he's 5-0 at this level, and 6-0 against the elite-level riders.

Follow Slade Long on Twitter @probullstats. 

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