Hill announced Sunday on social media that he has signed a contract with the Raiders, three days after the team placed tailback Devontae Booker on the reserve/COVID-19 list and two days after they waived undrafted rookie wide receiver Siaosi Mariner.
Financial details of the agreement weren't disclosed. The Raiders have yet to confirm the deal.
Hill, 27, last played in the NFL in the 2018 season, when he suffered a torn ACL during the Patriots' season-opening win over the Houston Texans. He spent the remainder of that season on injured reserve and was out of the league in 2019.
The Bengals selected Hill in the second round of the 2014 NFL Draft out of LSU. He spent his first four seasons in Cincinnati before signing a one-year pact with the Patriots as a free agent in March 2018.
As a rookie, Hill rushed for a career-high 1,124 yards with nine touchdowns. He followed his rookie year with a career-best 11 rushing scores in 2015, tying for the league lead.
In 55 career games with the Bengals and Patriots, he has recorded 2,898 yards and 29 touchdowns on 708 carries. He has added 68 receptions for 490 yards and one receiving touchdown.
Hill will join a Raiders backfield that consists of starter Josh Jacobs, veteran Jalen Richard, rookie Lynn Bowden Jr. and Booker, along with fullback Alec Ingold.