Dre Greenlaw ruled out with Achilles injury

49ers linebacker Dre Greenlaw will not return today, and he might not return for the start of next season, either.The team ruled out Greenlaw with an Achilles injury.The Pro Bowler was jogging back onto the field from the sideline after a punt when his leg gave out. He immediately went to the ground as teammates looked on with disbelief. He was carted to the training room, visibly upset as he departed.The team initially called him questionable to return.Demetrius Flannigan-Fowles and Oren Burks are attempting to replace Greenlaw, who finished with three tackles.Achilles tears are easily diagnosed and full healing typically takes 4-6 months, putting his availability for the start of next season in doubt.