49ers confirm Mykel Williams tore his ACL

49ers rookie defensive end Mykel Williams will miss the rest of the season after tearing his ACL in Sunday's 34-24 win over the Giants. Head coach Kyle Shanahan confirmed the diagnosis at a Monday press conference. Shanahan said Williams also suffered a lateral meniscus tear and that he's looking forward to the first-round pick making a full recovery. "I'm just really disappointed that he's not able to really continue developing through this year because I believe we got a hell of a player, who's going to really figure this out in the run game and the pass game," Shanahan said, via 49ersWebzone.com. "And he still will, but I hurt for him that he isn't going to do that over the next half of this year."Shanahan said they expect to get defensive end Bryce Huff back from a hamstring injury this week and that should help fill out the ranks in Williams' absence. Shanahan also said that wide receiver Ricky Pearsall (knee) and center Jake Brendel (hamstring) could return this week, but that there is no plan to open wide receiver Brandon Aiyuk's practice window.