The 49ers are potentially in the market for a defensive lineman.
The team worked out Tony McDaniel, Ahtyba Rubin, Kendall Langford and Jaye Howard on Wednesday, according to ESPN's Field Yates.
McDaniel started 15 games for the Seahawks in 2013, 14 in 2014 and 11 last season.
Rubin started all 32 regular season games for the Seahawks over the past two seasons.
The 49ers play in Seattle on Sunday.
Howard played for Seattle in 2012 and was with the Chiefs the prior four seasons.
Langford appeared in 135 games (113 starts) from 2008 through 2016.