A person with knowledge of the moves who requested anonymity because the Giants had not confirmed the agreements said the team also signed former Green Bay and Cincinnati offensive tackle Marshall Newhouse, Cowboys return specialist/receiver Dwayne Harris, and Jacksonville linebacker J.T. Thomas.
Vereen's contract is for three years and slightly more than $12 million. Casillas got a three-year $10.5 million deal, and Harris' deal is worth $17.5 million over five years, with $7.1 million is guaranteed. Newhouse's contract was for two years for a little more than $3 million. Thomas got a three-year deal for $12 million.
Adding Vereen gives Eli Manning a proven back who can catch passes, while Newhouse reunites with Giants offensive coordinator Ben McAdoo and might allow New York to move Justin Pugh from tackle to guard.
Vereen had 99 catches for 874 yards and six touchdowns over the past two seasons, including a game-high 11 catches for 64 yards in the Patriots' Super Bowl win over Seattle. It was the most catches by a running back in a Super Bowl.
The 26-year-old Vereen joins a Giants backfield that includes Rashad Jennings and second-year pro Andre Williams. Vereen ran 96 times last season for 391 yards and two touchdowns, starting six of 16 regular-season games.
Acquired in a trade with Tampa Bay during the season, the oft-injured Casillas played in eight regular-season games with 28 tackles for New England.
Harris had seven catches for 116 yards. He also had 30 kick returns for a 24.7 yard average and 30 punts return for a 9.2 yard average. He led the team with 18 special teams tackles.
Newhouse was a starter early in his career with the Packers but he has been more of a backup in recent seasons.
Thomas finished fourth on the Jaguars with 84 tackles. He led the team with two interceptions. The West Virginia product also plays in the middle, so that might end Mark Herzlich's chances of returning to the Giants.
The Giants created a little salary cap space earlier this week, reworking veteran middle linebacker Jon Beason's contract to save about $3 million. Beason only played four games last season because of a toe injury that required surgery.
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