Texans coach Gary Kubiak is optimistic Arian Foster will be ready for the regular-season opener. Foster re-aggravated a hamstring injury in Saturday's preseason game in San Francisco. The NFL's leading rusher in 2010, Foster left the field in the first quarter of Houston's 30-7 victory, favoring the left hamstring that he strained early in training camp. "Looks like we're dealing with the same thing we were dealing with at the start of camp," coach Gary Kubiak said. "Hopefully, we can get him back on the rehab train, and get him ready for opening day. He'll be day to day."