Dietrich-Smith spent the past three seasons with the Packers and has started 25 of 61 games he's appeared in at center and guard. He was one of two Green Bay offensive linemen to play in every game over the last two years.
The sixth-year pro is the seventh player to join the Bucs through free agency this week. Terms of the deal Friday were not disclosed.
Defensive acquisitions include pass rusher Michael Johnson, tackle Clinton McDonald and cornerback Alterraun Verner.
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