The San Francisco 49ers have signed safety C.J. Spillman to a three-year contract extension, Matt Maiocco of CSN Bay Area reports. According to Maiocco, the extension is worth $6 million and includes $1.8 million in guaranteed money. Originally signed by the San Diego Chargers as an undrafted free agent out of Marshall, Spillman totaled 19 tackles in 10 games with the Chargers before he was placed on waivers and claimed by the 49ers. Spillman has 31 tackles over the last 27 games, including 28 on special teams. Spillman was scheduled to be a restricted free agent this off-season. Source: Mac's Football Blog