Nnamdi Asomugha’s fourth-quarter knee injury Sunday apparently is serious enough that the 49ers have promoted rookie cornerback Darryl Morris from the practice squad. Morris, undrafted out of Texas State, fills a roster spot created by Aldon Smith’s move Monday to the non-football-injury list. To help with linebacker duties on the practice field, the 49ers signed D’Aundre Reed, a 2011 seventh-round pick by the Minnesota Vikings. Source:MercuryNews
