Blair is working his way back from an ACL tear late last season. He will need to spend the first six weeks on the PUP list before he can be activated.
Blair, 27, is a former fifth-round pick of the 49ers back in 2016. He played out his four-year, $2.61 million contract and made a base salary of $630,000 in 2019.
Blair re-signed with the 49ers on a one-year deal this offseason.
In 2019, Blair appeared in nine games for the 49ers and recorded 21 tackles, three sacks and one fumble recovery.