Trent Brown will not be returning to the New England Patriots.

The free agent left tackle is set to join the Oakland Raiders after agreeing to a four-year, $66 million contract with $36.75 million guaranteed, per ESPN's Adam Schefter.

Brown, 25, was acquired by the Patriots last April in a trade with the San Francisco 49ers. He performed at a high level for the Patriots throughout the regular season and the team's postseason run to a Super Bowl LIII title. However, at this price, it's not surprising the Patriots have moved on.

Who's next up on the depth chart for New England? Isaiah Wynn, one of the Patriots' 2018 first-round picks, could be the starting left tackle next season after missing his entire rookie year because of a torn Achilles. New England also could draft another offensive tackle in April; they have a league-high 12 picks, including six in the first three rounds.

Follow our NFL free agency live blog>>>

Click here to download the new MyTeams App by NBC Sports! Receive comprehensive coverage of your teams and stream the Celtics easily on your device.