Rob Jackson, here grabbing hold of Browns running back Ben Tate’s ankle on Monday, made some memorable plays for the Redskins, but not enough to keep his job. (Katherine Frey/The Washington Post)

The Washington Redskins have cut backup outside linebacker Rob Jackson, two people with knowledge of the situation said.

A seventh-year pro, Jackson had spent his entire career with Washington, serving primarily as Brian Orakpo’s backup on the right side.

Washington selected Jackson as a seventh-round pick out of Kansas State in 2008. He played sparingly on defense for the bulk of his career while also contributing on special teams. In 2012, Jackson started 14 games with Orakpo out for all but two games. Jackson recorded 37 tackles and 4.5 sacks and four interceptions – one of which he returned for a touchdown.

The Redskins this spring drafted outside linebacker Trent Murphy in the second round. Murphy has leapfrogged Jackson, joining Orakpo and starting left outside linebacker Ryan Kerrigan on the field on many pass-rushing downs.

Special teams play proved the deciding factor in Washington’s decision to release Jackson. Everette Brown, who joined the team early in training camp this summer, played in Jackson’s spot on some special teams units on Saturday.

Jackson ranks among the players released during this first round of cuts. Washington must trim its roster to 75 players by 4 p.m. on Tuesday. The final round of cuts then must take place by 4 p.m. Aug. 30.

Update, 5:30 p.m.:

Outside linebacker Adrian Robinson was the most notable of the other eight players that Washington parted ways with on Sunday.

The team also waived fullback Stephen Campbell, wide receiver Cody Hoffman, linebacker Jeremy Kimbrough, wide receiver Rashad Lawrence, safety Ross Madison, defensive end Jake McDonough, Robinson and defensive end Jeremy Towns.

The Redskins must cut another four players by Tuesday.

Follow Mike on Twitter for up-to-minute news on cuts. Here’s the NFL transaction wire, to track cuts around the NFL.

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