MODESTO — For the better part of the first half of Sierra’s showdown with Valley Oak League powerhouse Central Catholic Friday night, its offense was stuck in reverse. By the time the Timberwolves trotted off of David Patton Field to regroup, they had amassed only two offensive yards while allowing the Raiders almost 200. And while there wasn’t much good to take away from the 48-7 loss, Sierra head coach Chris Johnson considered the matchup to be a key component of a getting collectively better while proving its mettle against one the premier high school programs in all of California.