Providing a guy is equipped, defensive tackle doesn't look like it should be that difficult a position to learn. Line up across the big ugly on the other side, push, grunt, drive and snort until the best big man wins. Yet for NFL rookies, the defensive tackle position carries a steeper learning curve than wide receiver, offensive line or, dare we say, quarterback. Rookie quarterbacks have had a better go in recent years than rookie defensive tackles. The next sack or tackle for a loss that Dontari Poe, the No. 11 pick in the 2012 draft, gets for the Kansas City Chiefs will be his first in either category. Nick Fairley and Corey Liuget, the No. 13 and 18 picks in the 2011 draft, combined for only two sacks as rookies but improved to a total of 12½ sacks in year No. 2. Green Bay's B.J. Raji struggled as a rookie in 2009, then helped the Packers win the Super Bowl in 2010. Which brings us to the Broncos' rookie minicamp this weekend and to their first-round draft pick, defensive tackle Sylvester Williams. Why, Sly, do defensive tackles usually struggle as rookies? "The biggest thing, just from watching film in the trenches, is the strength," Williams said Friday. "You go from playing with guys in college that you may have played against (who are) freshmen, to coming in here and playing against grown men. A lot of them have families and kids they have to feed. So it's a different ballgame. It's an adjustment period that everybody has to make."