49ers add Okuayinonu to active roster, place Hargrave, Robinson on IR

Defensive end Sam Okuayinonu is back on the 49ers' active roster after initially making the cut to 53 players at the end of training camp. The 49ers on Saturday promoted Okuayinonu while placing defensive tackle Javon Hargrave and linebacker Curtis Robinson on injured reserve. The 49ers also elevated two undrafted rookies from the practice squad: defensive tackle Evan Anderson and safety Jaylen Mahoney. Both players will revert back to the practice squad on Monday. Okuayinonu, Anderson and Mahoney are expected to be in uniform Sunday when the 49ers face the New England Patriots at Levi's Stadium. Anderson and Mahoney are in line to make their NFL regular-season debuts. Okuayinonu has appeared in two games this season. He has three tackles and a sack. He had a spot on the 49ers' initial 53-man roster but was waived one day later in a series of moves. Anderson (6-foot-3, 326 pounds) appeared in 39 games during his four-year career at Florida Atlantic. In his final college season, Anderson appeared in 12 games and had 57 tackles, 5.5 tackles for loss, 3.5 sacks and one forced fumble. Anderson provides depth at defensive tackle with Hargrave out and presumptive starter Jordan Elliott...