Seahawks signing ex-49ers starting CB Dontae Johnson

SEATTLE -- The Seahawks are adding some much-needed starting experience at cornerback by signing former San Francisco 49er Dontae Johnson, a source confirms to ESPN.

Terms of Johnson's deal, which was first reported by the NFL Network, were not immediately available.

The 26-year-old Johnson started 22 games over four seasons in San Francisco, which drafted him in the fourth round out of North Carolina State in 2014. That included 16 starts last season, though Johnson's struggles in coverage led to a benching in a December win over the Houston Texans.

The Seahawks had a large void at cornerback after releasing Richard Sherman last month (he later signed with the 49ers). With DeShawn Shead also…