Rapoport adds that Jackson’s extension includes a $9 million signing bonus along with $7.075M in additional guarantees.
Jackson told reporters on Tuesday that the Seahawks made an adjustment to his contract.
The Raiders were reportedly prepared to release Jackson before the Seahawks stepped up with an offer to get him a few weeks ago.
Jackson, 29, is a former third-round pick of the Raiders back in 2014. He was in the final year of his four-year, $2.952 million contract when he agreed to a new five-year, $56 million extension that included $26 million guaranteed with the Raiders in 2017.
Jackson made a base salary of $9.35 million for the 2020 season and was set to make that same amount in 2021 when the Raiders traded him to the Seahawks for a 2021 fifth-round pick.
In 2020, Jackson started all 16 games for the Raiders. Pro Football Focus has him rated as the No. 40 guard out of 80 qualifying players.