NAPA -- The situation might have called for the prototypical big back -- ball on the Arizona 1-yard line.But twice Raiders offensive coordinator Greg Knapp called for Darren McFadden to pound the ball up the middle. And twice McFadden was stopped for no gain. No matter to Knapp."Ive always had a belief that the No. 1 back can still be the goal-line back, doesnt have to necessarily be a bigger, stronger guy," said Knapp, speaking to reporters for the first time in training camp. "My experience tells me so, last couple years it was Arian Foster (who) had a lot of success. Warrick Dunn was one the best inside-tackle runners Ive ever been around as a coach. Its not just the back that requires the execution of the play. So it didnt bother me to have him in there, we just didnt get it executed across the board."Got it? And yes, Knapp's play-calling against Dallas and Arizona these first two exhibition games should look little like what he'll do come the regular season. And no, the Raiders have not worried about overworking McFadden, who has been felled by injury in each of his first four seasons in the NFL and coming off a season-ending Lisfranc sprain to his right foot."We knew last week wed have limited time to play with him," Knapp said. "Hes only going to play a limited amount of time so I wanted to make sure he got some touches so hes ready for the season. Its a fine line, how much do you play him, how many touches does he get."And when we got down in that (goal-line) situationhe wants to be a football player, too. He wants to score touchdowns and theres a chance to score touchdowns there. So to me it was just the ebb and flow of the game, I never second-guessed who would play in that position. Im fine with that in training camp as we assess the preseason and evaluate our personnel and our scheme, then well make a decision on the regular season to change it up. But right now I have no regrets about doing that."Knapp was the Raiders' offensive coordinator in McFadden's rookie season of 2008. So how different is McFadden five years later?"His ability to see the hole is exciting," Knapp said. "Ive seen the growth in his vision in the run game. Where he identifies, 'OK, heres my chance to do the one-cut down hill, or one-cut bounce move.'"That parts been exciting as well as his blitz pickups. Hes got a better understanding of seeing the safety rotation and identifying blitzes and thats made him a more well-rounded running back so we can play him on all downs."Yes, even on the goal line.