Getty (Photo by Harry How/Getty Images) The San Francisco 49ers have arguably one of the best QB2s in the league with Mac Jones backing up Brock Purdy. Jones showed last season that he can come in and keep the ship afloat while also playing well. Last season, Jones played 545 total snaps for the Niners,  allowing him to earn a 77.1 overall PFF grade . Additionally, he threw for 2,151 yards and 13 touchdowns, while recording six interceptions. Moreover, Jones registered eight big-time throws and