49ers rookie Mykel Williams out for season with knee injury

Mykel Williams, the San Francisco 49ers' first round draft pick, will miss the remainder of the season after sustaining a torn anterior cruciate ligament and a torn lateral meniscus in his right knee late in Sunday’s 34-24 road win over the New York Giants, coach Kyle Shanahan said Monday. The injury occurred with about four minutes remaining at MetLife Stadium as Williams pressured Giants quarterback Jaxson Dart and then grasped at his right knee before leaving the field.

Williams, who entered the game as a starter, walked off under his own power but did not return. Shanahan said tests on Monday confirmed the initial fears. “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,” Shanahan said, adding that he expects Williams to make a full recovery. After the game he had offered guarded optimism, saying, “You never know until Monday’s MRI. Hopefully it’s not the worst. If it is, it stinks for this year, but you’ll be back next year and it won’t affect you at all.”

Through nine games, Williams had 20 tackles, one sack and four tackles for loss, and coaches credited him with an immediate impact...