The 5-foot-11, 220-pound Ridley has played in 60 career NFL games (26 starts), rushing for 2,907 yards and 22 touchdowns in his time with the New York Jets (2015) and the New England Patriots (2011-14).
The 27-year-old Ridley also has 27 career receptions for 144 yards and seven kickoff returns for 152 yards. He has seen action in five postseason contests (one start), totaling 242 rushing yards and three touchdowns with two receptions for 17 yards. He was a member of New England's Super Bowl XLIX winning team.
In 2015, Ridley played in eight games (one start) in his one season with the Jets and compiled 36 carries for 90 yards and caught four passes.
Ridley was originally selected by the Patriots in the third round of the 2011 NFL Draft out of LSU. He rushed for 1,263 yards and 12 touchdowns in his second season in New England in 2012.
Meanwhle, the Colts trimmed their roster prior to Tuesday's league-mandated deadline of 75 players, including waiving offensive guard Eric Herman.
The Colts also waived wide receiver Justin Berger, safety Alden Darby, defensive tackle Ricky Lumpkin, tight end Mike Miller, running back Chase Price, cornerback Winston Rose, defensive end Delvon Simmons, wide receiver Josh Stangby and inside linebacker Junior Sylvestre.
The 6-4, 320-pound Herman signed with the Colts as a free agent on Aug. 21. He spent time on the Baltimore Ravens' practice squad in 2015. Herman was on the New York Giants' active roster and practice squad in 2013 and 2014, but did not see any game action. He was originally selected by the Giants in the seventh round of the 2013 draft after starting 50 games at Ohio University.
The 6-2, 198-pound Berger signed with the Colts as an undrafted free agent on Aug. 22. Collegiately, he played in 27 games at Wyoming and finished with seven receptions for 90 yards and one touchdown and one carry for eight yards and one touchdown.
The 5-10, 194-pound Darby signed with Indianapolis as a free agent on Aug. 17. He spent most of the 2015 season on the New Orleans Saints' practice squad. Collegiately, Darby played in 50 games (28 starts) at Arizona State and totaled 217 tackles, 8.5 tackles for loss, 26 passes defensed, 10 interceptions, three forced fumbles and four fumble recoveries.
The 6-3, 300-pound Lumpkin signed a reserve/future contract with Indianapolis on Jan. 19. He has competed in seven career games between the Arizona Cardinals (2011-12) and the Oakland Raiders (2013-14), totaling 10 career tackles and one sack.
The 6-6, 255-pound Miller signed with the Colts as a free agent on Aug. 21 after being waived by the team on July 29. He originally signed with Indianapolis as an undrafted free agent on May 3. Miller played in 27 games (20 starts) at Taylor University and finished his career with 80 receptions for 959 yards and seven touchdowns.
The 5-8, 200-pound Price signed with Indianapolis as an undrafted free agent on Aug. 11. Collegiately, he played in 50 games at San Diego State and totaled 377 carries for 1,896 yards and 12 touchdowns and 34 receptions for 247 yards and one touchdown.
The 6-0, 180-pound Rose signed with the Colts as a free agent on May 18. Collegiately, he played in 25 games (14 starts) at New Mexico State and finished with 105 tackles, three tackles for loss, 13 passes defensed, five interceptions and one fumble recovery.
The 6-5, 295-pound Simmons signed with Indianapolis as an undrafted free agent on May 2. He played in 27 games (24 starts) at USC, notching 101 tackles, 13 tackles for loss, five sacks, three passes defensed, two blocked field goals, two forced fumbles and one fumble recovery.
The 5-10, 185-pound Stangby signed a reserve/future contract with the Colts on Jan. 5. He spent the final two weeks of the 2015 regular season on Indianapolis' practice squad. Stangby previously spent time with the Portland Thunder of the Arena Football League in 2015. Collegiately, he played two seasons at Ottawa University (Kansas), where he totaled 84 receptions for 1,465 yards and 18 touchdowns.
The 6-0, 242-pound Sylvestre signed with Indianapolis as an undrafted free agent on May 5, 2015. He spent the entire 2015 season on the Colts' injured reserve list. Collegiately, Sylvestre played at Toledo and finished his career with 286 tackles, 7.5 sacks, one interception, three forced fumbles and eight passes defensed.
Indianapolis must reduce its roster from 90 to 75 players by Tuesday at 4 p.m. ET and then to 53 by Saturday at 4 p.m. ET.