The 49ers have agreed to terms with defensive tackle Sebastian Joseph-Day, Jason McCourty of NFL Media reports.
The Chargers waived Joseph-Day last week, and he cleared waivers.
Joseph-Day was a team captain for the Chargers this season and started all 14 games before his release, totaling three sacks, 31 tackles, three tackles for loss and 11 quarterback hits.
Joseph-Day, 28, will help fill in at the position alongside Javon Hargrave as Arik Armstead continues to work his way back from knee and foot injuries.
He has 11 sacks and 21 tackles for loss in 69 games in his career that includes three seasons with the Rams and two with Chargers.
