Plummer, 28, has not played since Oct. 17 and been bothered by neck problems since last season.
He lasted only six starts this season after re-signing March 5 for $25 million US over five years.
Plummer has totalled 285 tackles, 12 interceptions, a fumble recovery and a touchdown in 67 games, including 66 starts, since being drafted 24th overall by San Francisco in 2000.
Niners
The Niners have been without either starting cornerback since Week 6, losing Mike Rumph with a broken arm two weeks earlier.
with files from Sports Network

