As of the start of last Sundays game against the Eagles, Erik Cook had been on an NFL roster for eight games. He was on the inactive list for four of them and then he was active but did not play in the next four.That changed in a hurry at the end of the Redskins first offensive series last Sunday. Starting left guard Kory Lichtensteiger went out of the game with a knee injury. Center Will Montgomery moved over the left guard and Cook went in at center.Later it was revealed that Lichtensteiger tore both his ACL and MCL and he will be out for the season. That means that Cook is now the Redskins starting center.At 6-6, Cook becomes the tallest starting center in the league. But he almost didnt make it into the game last Sunday.Mike Shanahan revealed that he Cook had sustained a strained calf prior to the game and that it looked like he might not be able to play. According to Cook, the problem had started at practice earlier in the week.I tweaked it a little during practice but it wasnt anything to worry about, Cook said. In warmups I did something wrong to it.When the call came for him to enter the game, Cook was a bit unsure.I was a little hesitant (about going into the game) but I got out there, Cook said. The calf felt good and I played to the best of my ability.Cook was a seventh-round draft pick out of New Mexico. At 6-feet-6 he will be the tallest starting center in the league.The height can be a disadvantage in the interior of the trenches in the NFL. It can be a challenge to engage defensive tackles, who are usually shorter, without having them get under their pads. Once a defensive linemen gets there, the battle usually is decided in the defenders favor. There also is a tendency for the taller blockers to bend at the waist to made contact with the defender, making them lose their balance.The leverage at times can be an issue for Erik but hes done a nice job, said offensive line coach Chris Foerster. In the game on Sunday he was able to hold his own. Its at time harder for that guy but hes getting used to playing the position.Cook has more than just leverage to worry about. The center makes the pass protection calls. Thats a big responsibility but Montgomery, who made the calls all year up until Lichtensteiger went out, thinks that Cook is up to the challenge.He just has to go in there, make the right calls, get us all on the same page, said Montgomery. Hes been doing it on scout team and in the preseason so just find the Mike the middle linebacker, whose positioning key to protection calls, and then lets go. Hes a bright guy, he shouldnt have to hard of a problem with that.Cook is glad to have Montgomery lining up alongside him. Its definitely an advantage having Monty there, said Cook. Hes had the five games at center so he helps me out if he sees something wrong.Kyle Shanahan that although having to play backups is a challenge, he has confidence in Cook. Hes come a long way. . . I dont think the game is too big for him, the offensive coordinator said. If Erik gets in there hell battle you. Hes not going to look great right away.When its all said and done, he does his job.Rich Tandler blogs about the Redskins at www.RealRedskins.com. You can reach him by email at RTandlerCSN@comcast.net and follow him on Twitter @Rich_Tandler.