This marks the second time the Steelers had reached an extension with one of their linebackers after hammering out a six-year, $61.5 million pact with linebacker LaMarr Woodley.
Timmons is a key contributor to one of the NFL's top defenses.
The former Florida State standout has made a sound transition to the NFL after a somewhat bumpy rookie season.
With James Harrison and James Farrior up in years, the Steelers have two young linebacker standouts under contract for the next several years.
For more coverage of the Steelers, go to Steel City Insider at www.pit.scout.com.
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Steelers sign Timmons to $50 million
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