In 2010, Adams competed for the job as the starting free safety against Abram Elam and Ray Ventrone during training camp. Head coach Eric Mangini named Adams the backup free safety to start the season, behind Abram Elam. He started in the Cleveland Browns' at the Tampa Bay Buccaneers and collected seven combined tackles, made a season-high three pass deflections, and an interception in their 17–14 loss. Adams was inactive for the Browns' Week 11 loss at the Jacksonville Jaguars due to an abdomen injury. On December 5, 2010, Adams recorded three combined tackles, a pass deflection, and an interception in the Browns' 13–10 victory at the Miami Dolphins in Week 13. He intercepted a pass by quarterback Chad Henne that was deflected by Browns defensive lineman David Bowens and returned it 25-yards to the two-yard line. His interception set up a 23-yard game-winning field goal by Phil Dawson as time expired in the fourth quarter. He finished the season with 45 combined tackles (39 solo), six pass deflections, two interceptions, and a sack in 15 games and two starts. On January 4, 2011, the Cleveland Browns fired head coach Eric Mangini after the Browns finished with a 5–11 record in 2010. During training camp, Adams competed to be the starting free safety against Usama Young. Head coach Pat Shurmur named Adams the starter to begin the regular season, along with strong safety T. J. Ward. In Week 4, he made two solo tackles, a pass deflection, and intercepted a pass by Jake Locker during a 31–13 loss to the Tennessee Titans. It marked his second consecutive game with an interception. On December 8, 2011, Adams collected a season-high ten combined tackles (six solo), broke up a pass, and intercepted a pass by Ben Roethlisberger in the Browns' 14–3 loss at the Pittsburgh Steelers in Week 14. He completed the season with 64 combined tackles (44 solo), six pass deflections, and three interceptions in 16 games and 16 starts. Adams became an unrestricted free agent after the 2011 season and did not receive a contract offer from the Browns although he expressed a desire to return. He reportedly received interest from four teams, including the Denver Broncos. On March 15, 2012, the Denver Broncos signed Adams to a two-year, $4 million contract with $250,000 guaranteed. During training camp, he competed to be a starting safety against Rahim Moore, Duke Ihenacho, and Quinton Carter.