Niners place rookie LB Borland on IR

Santa Clara, CA ( - San Francisco 49ers rookie linebacker Chris Borland will miss the final two games of the season because of an ankle injury.

Borland, San Francisco's leading tackler, was hurt in last week's loss to Seattle. The 49ers have already been eliminated from postseason contention.

The third-round pick from Wisconsin didn't crack the starting lineup until Week 7, but still has a team-high 128 tackles with two interceptions, one sack and one fumble recovery. He was the NFL's top defensive rookie for November when he became the first player in 20 years to register 70 tackles and two interceptions in a calendar month.

San Francisco filled the roster spot by promoting linebacker Chase Thomas from the practice squad.