New York Giants offensive tackle David Diehl had surgery Wednesday on what the team called his “unstable right thumb” and is expected to miss six weeks, including the season opening game against the Dallas Cowboys.Diehl, in his 11th season, had practiced Tuesday with a cast on his hand before additional tests confirmed that surgery was necessary.It’s another blow to the Giants’ offensive line. Starting center David Baas has a sprained left MCL and the knee injury is expected to keep him sidelined 2-4 weeks.Briefly • Retired: Running back Terrance Ganaway, the Jets’ sixth-round pick in 2012 out of Baylor, has decided to retire and go to graduate school. Ganaway, among the Jets’ last cuts, was picked up by the Rams and was on the active roster all season. He was in three games but had no carries or catches. • Steelers: Rookie running back Le’Veon Bell is expected to miss 6-8 weeks with a Lisfranc injury to his right foot, according to ESPN. • Texans: Running back Arian Foster, sidelined all summer with a calf injury and back pain, was activated off the physically unable to perform list. He isn’t likely to play until the season opener against the Chargers. • Saints: Offensive tackle Jason Smith, a graduate of Dallas W.T. White High School and No. 2 overall draft pick in 2009 out of Baylor, was cut after signing in April. • Redskins: Quarterback Kirk Cousins has no significant ligament damage in his right foot and is expected to be available for the Sept. 9 season opener with the Eagles, according to the Washington Post. His availability isn’t likely for Saturday’s exhibition game against the Bills, leaving Rex Grossman and Pat White to split snaps. • Giants: Cornerback Terrell Thomas, who missed the past two seasons with ACL tears in his knee, will play Saturday against the Jets, his first game since August 22, 2011. • Cardinals: Kicker Dan Carpenter, released a week ago by the Dolphins, signed a one-year contract with Arizona. Carpenter will be in competition with Jay Feely, who lost his job to Carpenter in Miami in 2008. • Jets: Fullback Lex Hilliard was put on season-ending injured reserve with a broken shoulder blade. • Colts: Running back Delone Carter was traded to the Ravens for receiver David Reed.