MIAMI -- The Miami Dolphins have agreed to a three-year contract extension with offensive linemen Austin Jackson, a source confirmed to ESPN, ensuring the 2020 first-round pick doesn't hit free agency this coming offseason.

The extension is worth $36 million and includes $20.7 million in guaranteed money for the team's starting right tackle, per the source.

Miami selected Jackson with the 18th overall pick in the 2020 NFL draft and slotted him in as its starting left tackle. However, the team declined his fifth-year option this past offseason after inconsistent play, multiple position changes and injuries during his first three seasons.

Despite his struggles in his first two seasons, Jackson showed promise during his first training camp under head coach Mike McDaniel in 2022, after a move to right tackle. An ankle injury sidelined him for all but two games during the regular season, though, keeping him from building on his summer momentum.

He replicated his training camp performance in 2023, fully healthy, and has not missed a snap for the Dolphins this season. He has allowed just two sacks in 740 snaps protecting quarterback Tua Tagovailoa's blind side, and has been a critical component of an offensive line that has allowed the fourth-fewest sacks in the NFL this season.

Jackson is the first of several players the Dolphins must decide whether to re-sign before the 2024 season, a list that includes defensive tackle Christian Wilkins, right guard Robert Hunt, linebacker Andrew Van Ginkel and center Connor Williams, who held out of the team's mandatory minicamp in pursuit of a new contract.

NFL Network first reported Jackson's deal.