Pau Gasol suffered a mild to moderate left hamstring strain, the results of ultrasound and MRI exams revealed today. Dr. Steve Lombardo examined Gasol, whose status for Tuesday’s game against the Houston Rockets was termed doubtful. He will be listed as day-to-day for future games and practices. He was injured during the first quarter of the Lakers’ 35-point victory over the Dallas Mavericks on Sunday. The 7-foot power forward/center sat out the season’s first 11 games because of a strained right hamstring.