Acker, 26, is a former sixth-round pick of the 49ers back in 2014. San Francisco traded him to the Chiefs at the start of the 2016 season for a 2018 seventh-round pick.
Acker played out the final year of his four-year, $2.340 million rookie contract before signing on with the Colts this summer. His stay in Indianapolis was brief and he signed on with the Jaguars soon after before being placed on injured reserve coming out of the preseason.
In 2017, Acker appeared in all 16 games for the Chiefs and recorded 23 tackles, one interception and a pass defense.