The contract, confirmed by Butler's agent and a team offfcial, is worth about $3.9 million, but an annual financial breakdown of the deal was not immediately available.
The 41st overall choice in the draft, Butler is only the second player chosen in the second round to reach a contract agreement, joining Philadelphia Eagles tailback LeSean McCoy. He is just the second of New England's 12 picks in 2009 to come to terms.
Regarded by many as the top coverage defender in the draft pool, Butler inexplicably slipped to the second round, where the Patriots gladly stopped his free fall. As a rookie, Butler should compete for playing time in nickel situations, and could contribute on special teams, likely as a kickoff return man.
New England finished 12th against the pass in 2008, but surrendered 27 touchdown passes, the second most in the league. The club has made revamping the cornerback position a priority in the offseason. During the draft, the Patriots traded starter Ellis Hobbs to the Eagles. The year before, starter Asante Samuel departed to the Eagles as a free agent.
The Patriots signed veterans Shawn Springs and Leigh Bodden as free agents in the offseason, and that pair is likely to start. The club is also counting on young veterans such as Terrence Wheatley, Jonathan Wilhite, and Mike Richardson. Butler should fit well with that group.
A four-year starter in college and a captain for two seasons, Butler posted 108 tackles, 9½ tackles for loss, 14 interceptions and 26 passes defensed at Connecticut. And that includes not intercepting a pass his senior season, when opponents avoided throwing at him. Unofficially, Butler surrendered no passing touchdowns in 2008.
Butler also ran back kickoffs, averaging 25.4 yards on 35 returns for his career.
At 5-feet-11 and 183 pounds, Butler possesses good size for the position, and his quickness and speed are strong suits. At the NFL combine in February, he was timed at 4.46 seconds, the fastest of any cornerback invited to the workouts. In private auditions, he has been timed as fast as 4.41 seconds. Butler has also posted a 43-inch vertical jump.
Len Pasquarelli is a senior NFL writer for ESPN.com.