49ers roster moves: O-lineman, receiver added; Corey Kiner, Demone Harris cut

The San Francisco 49ers have made several roster moves, signing offensive lineman Michael Dunn and wide receiver Malik Knowles to one-year deals. To create space, the team released defensive lineman Demone Harris and waived/injured running back Corey Kiner.

Dunn was one of three offensive linemen the 49ers worked out on Tuesday before agreeing to terms. The 30-year-old has starting experience, adding depth to the offensive line.

Kiner sustained a high-ankle sprain in Saturday's preseason matchup against t he Las Vegas Raiders. He was expected to miss at least a month.

The 49ers Communications staff provided the following rundown.

Dunn (6-5, 315) originally entered the NFL after signing with the Los Angeles Rams as an undrafted free agent on June 16, 2017. Throughout his eight-year NFL career with the Rams (2017-18), Jacksonville Jaguars (2018-19), Miami Dolphins (2019), and Cleveland Browns (2020-24), he has appeared in 53 regular-season games (nine starts) and two postseason contests (one start). In 2024, Dunn appeared in 13 games (three starts) with the Browns.

A 30-year-old native of Bethesda, MD, Dunn attended the University of Maryland for five seasons (2012-16), where he appeared in 46 games.

Knowles (6-2, 196) originally entered the NFL after signing with the Minnesota Vikings as an undrafted free agent on May 1, 2023. He has spent his two-year career with the Vikings (2023-24) and Green Bay Packers (2024). He signed with San Francisco on June 3, 2025, prior to being waived by the team on July 31.

A 25-year-old native of Mansfield, TX, Knowles attended Kansas State University (2018-22), where he appeared in 51 games (39 starts) and totaled 127 receptions for 1,867 yards and 14 touchdowns through the air to go along with 36 carries for 440 yards and four touchdowns on the ground. He earned Second-Team All-Big 12 in 2021.

Harris (6-4, 265) originally signed with the team on August 14, 2025. Kiner (5-9, 209) originally signed as an undrafted free agent with the team on April 28, 2025.