Injuries are beginning to mount for the Kansas City Chiefs just three days into padded practices at training camp. Already with holes at cornerback, the Chiefs are down three promising options after Alex Brown tore his ACL on Saturday and Lavert Hill and Antonio Hamilton were held out Sunday. Hamilton has a groin strain and Hill a hamstring injury. Two other crucial pieces to their Super Bowl run last season also are out. Left tackle Eric Fisher sustained a concussion and is going through the league’s protocol, while wide receiver Sammy Watkins has been slowed by a groin strain.