The contract carries a total value of $84 million and includes $44 million in guaranteed money, according to a league source.
The former Wisconsin standout has excellent technique and durability, never missing a start since entering the NFL.
Thomas was drawing to the close of a five-year, $42.5 million rookie deal.
Now, Thomas can remain with the Browns for the long haul.
For more coverage of the Browns, go to the Orange and Brown Report at www.cle.sc
Browns lock up Joe Thomas
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