After releasing veteran Nick Collins because of his neck injury, the Packers enter OTAs with safeties that range from unproven (rookie Jerron McMillian, 2011 undrafted FA M.D. Jennings, third-year practice-squad player Anthony Levine), to inconsistent (2010 third-rounder Morgan Burnett), to unappealing (journeyman Charlie Peprah). “I like our young safeties,” coach Mike McCarthy said.