Walker (back) remains hopeful he won't require a trip to the disabled list, Rob Biertempfel of the Pittsburgh Tribune reports. Walker has missed eight straight games for the Pirates, but insists on continuing to go through with his regular pre-game routine. The hope is that one of these days he'll respond well to taking batting practice, and be ready to be re-inserted into the lineup. If he does end up requiring a DL stint, it could be backdated to Aug. 10, as he made a pinch-hit appearance on Aug. 9. Michael Martinez and Jayson Nix have been covering second base in his absence.