The Astros have placed Carlos Corporan on the 7-day concussion list after he was struck in the head by a foul tip in Monday’s loss to the Rangers. The Astros also designated pitcher Wade LeBlanc for assignment, just one day after calling him up. To fill the roster spots, the team has brought up RHP_ David Martinez from Oklahoma City and catcher Max Stassi from Corpus Christi. Martinez, 26, had spent most of the 2013 season at Corpus before being promoted to Oklahoma City earlier this month. At the two levels combined, he is 14-3 with a 2.20 ERA in 28 appearances (20 starts) with two complete games. Stassi, 22, [...]