Keep Mangini or go after Vrabel? 49ers' Kelly has options

Daily 49ers blog for NBC Bay Area website: New 49ers head coach Chip Kelly may keep defensive coordinator Eric Mangini, but he has an interview now with Texans LBs coach Mike Vrabel. http://www.nbcbayarea.com/news/sports/Niners-Chip-Kelly-Has-Options-for-his-Defensive-Coordinator-365774981.html