TAMPA — At 6 feet, 213 pounds, Charles Sims looks like a power runner, a bone-jarring back who doesn't run to daylight as much as he punches a hole in the wall to create it. Then when tacklers brace for contact, he turns on the jets and makes moves that would cause a chiropractor to grimace."I just want to mix it up," Sims said of his running style. "You want to give them a move every now and then. Then to keep them on their toes, you just want to go straight forward. You give them the wiggle and the next time they expect the wiggle and I just go right through them."A change of pace was also what the Bucs sought when they drafted Sims in the third round from West Virginia.You wouldn't expect the selection of Sims to be greeted with open arms in the running backs room. The Bucs already had a logjam of ballcarriers when the team ignored more glaring needs such as guard to add to a position of strength.The depth was born from injury. Starter Doug Martin, who rushed for 1,454 yards as a rookie, tore the labrum in his left shoulder in Week 6 at Atlanta last season and was done. Backup Mike James broke his ankle three games later. Bobby Rainey, claimed off waivers from the Browns, carried the rushing load the rest of the way. Each finished the season with more than 500 yards rushing.Martin and Rainey are 5-9 and 5-8, respectively. James seems to tower over them at 5-11. None is as physically imposing as Sims, who reminds former Bears and now Bucs running backs coach Tim Spencer of Chicago's Matt Forte."I think you can tell, especially at skill positions, does a guy have it?" coach Lovie Smith said. "Charles Sims, I would say, has it. He hasn't played a game and right now we're not live an awful lot. But you can see enough in him to like his future with us. Just talking about it, that's the last thing. He can carry the ball or he can catch the ball. Protections for any young back, that's the thing that they will have the most trouble with early on. But he's picked things up fairly well quickly."Sims, 23, had to be fast on his feet to pick up a new offense, transferring to West Virginia as a senior after three solid seasons at Houston. Mountaineers coach Dana Holgorsen had been the Cougars' offensive coordinator when Sims was a freshman.All told, Sims caught 203 passes in his career, making him a perfect fit for the Bucs offense under coordinator Jeff Tedford."He's a big guy that's very elusive, has great feet, really good skills running or catching the football and running routes," Tedford said. "He understands pass protections. For a young guy, he's picked that up really, really well."Sims puts it another way. "You can't get the quarterback hit or you won't be playing. That's the most important thing, pass blocking," he said.The addition of Sims has been good for Martin, who averaged only 3.6 yards per carry before his injury. Martin doesn't seem too concerned that Sims could significantly cut into his carries."Nobody likes rotten apples," Martin said about the prospect of staying fresher this season.Sims, a Houston native, runs a 4.48 40-yard dash, making him one of the fastest players on the team. He grew up idolizing Barry Sanders but his running style is more like James Wilder's."We are very deep there," Tedford said of running back. "I'm really impressed by their knowledge. They all bring something different. They all have skill. They all catch the football really well. They're smart and they can run between the tackles and they have speed outside. They're really versatile guys. It's a good group of guys to work with and I'm anxious to watch them in the game."But after practice one day this week, it was obvious Sims was still a rookie. The only thing he carried after practice was a veteran's shoulder pads and helmet.