Chris Borland's standout rookie season has come to an end as the inside linebacker was placed on injured reserve before the San Francisco 49ers' home game against the San Diego Chargers on Saturday.
Linebacker Chase Thomas was promoted from the practice squad and he will wear No. 58.
Borland injured his left ankle on the final play of the first half in last week's loss at the Seattle Seahawks. He replaced the injured Patrick Willis in the starting lineup and has a team-leading 107 tackles in 14 games, eight starts. The two-time Pepsi rookie of the week and the NFC's defensive player of the Week for Week 11 was also the NFL defensive rookie of the month for November after being the first player in 20 years to have 70 tackles and two intercepotions in a calendar month.
He also had two interceptions, five passes defensed, a sack and a fumble recovery on the season. Nick Moody will replace Borland in the starting lineup.
