Head coach Kyle Shanahan has ruled Pettis (knee) out for the season finale Sunday against the Rams, Nick Wagoner of ESPN.com reports.
Pettis sprained his MCL during this past weekend's loss to Chicago. His season now over, the 2018 second-rounder will get an early start to the offseason with much to build upon after averaging four receptions for 71.8 yards with four touchdowns over the final five games of the season. The impending return of Jimmy Garoppolo (knee) at quarterback in 2019 makes Pettis' future even brighter.