49ers announce Jaylon Allen signing, place Tarron Jackson on IR

The San Francisco 49ers have officially announced the signing of defensive end Jaylon Allen to a one-year deal. To make room on the roster, the team placed defensive lineman Tarron Jackson on injured reserve after he suffered a neck injury during Sunday's practice.

The 49ers Communications staff provided the following rundown.

Allen (6-3, 240) originally entered the NFL after signing with the Denver Broncos as an undrafted rookie free agent on May 10, 2024. Following his release from Denver on August 14, 2024, he spent time with the Memphis Showboats and the Arlington Renegades of the United Football League (UFL). In 2025 with the Showboats, he appeared in 10 games (nine starts) and registered 27 tackles, 1.5 sacks, one tackle for loss, and one forced fumble.

A 25-year-old native of Humble, TX, Allen attended the University of Memphis for five seasons (2019-23), where he appeared in 60 games and registered 150 tackles, 13.0 sacks, five passes defensed, three fumble recoveries, two forced fumbles, and one interception, and was named Second-Team All-AAC in 2023.

Jackson (6-2, 254) originally signed with the team on January 2, 2025.

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