Parker has a herniated disc that will require surgery and, since fellow defensive tackle Shaun Rogers has also been declared out for the season because of a blood clot in his leg, the team added two defensive tackles.
Rogers has not been moved off the roster yet, but the release of defensive back Janzen Jackson earlier in the week gave the Giants roster space to add both Wilson and Powell.
Powell (6-foot-3, 312 pounds) was drafted by Denver out of Virginia Tech in the fifth round in 2008 and has primarily been on practice squads for his entire career. He played 38 snaps for the Atlanta Falcons last season, but has registered only one tackle in the league.
Wilson (6-foot-1, 305 pounds) is a former Michigan State Spartan who ended up at Akron after being convicted of two counts of misdemeanor assault and battery. The New Jersey native went undrafted this year.
Both are expected to be in uniform on Sunday when the Giants "visit" the New York Jets at MetLife Stadium for a preseason game.
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