Rob Jackson had three straight games with a sack in 2012, forced into action due to a rash of injuries.
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Washington Redskins linebacker Rob Jackson has been suspended four games without pay for violating the NFL's substance abuse policy.

The league said Wednesday night that Jackson will miss the first four games of the regular season.

The Redskins re-signed Jackson to a one-year contract with a $715,000 base salary this month to keep him from becoming a restricted free agent.

Jackson was selected in the seventh-round by the Redskins in 2008. He started 14 games last year and had 4 1/2 sacks filling in for injured outside linebacker Brian Orakpo.

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