Lane Johnson and the Eagles agreed to a 4-year, $72 million contract extension Friday, an NFL source said.

Johnson’s deal includes $54.595 million guaranteed and makes the right tackle the highest-paid offensive lineman in league history in terms of per-year average and guarantees, per the source. He had two more years left on the original five-year extension he signed in Jan. 2016, but the Eagles have been locking up some of their core players over the last month.

Right guard Brandon Brooks, kicker Jake Elliott and long snapper Rick Lovato recently agreed to long-term extensions. Tight end Zach Ertz and safety Malcolm Jenkins could be next on the Eagles’ to-do list.

The 29-year-old Johnson has developed into arguably the best right tackle in the league. Some might consider him the best at either side. He has played in each of the last two Pro Bowls and was named a first team Associated Press all pro after the 2017 season.

Johnson likely would have made the switch to the left for most teams, but has played with Jason Peters, one of the best left tackles in the NFL each year, his whole career.

“I’m fortunate to be where I’m at,” Johnson said. “Jason playing left, probably being the best, or one of the best if not the best to ever play. I’ve had a lot of great influences over my career and throughout. I never thought I’d be a right tackle my whole career, but here I am and that’s really where I plan to stay."

Johnson’s new extension would take him to his 35-year-old season. The 2013 first-round pick said he hopes to finish his career in the same place it started.

“My whole goal is to stay here and be an Eagle the rest of my career,” Johnson said. “So, moving forward, that’s all I want to be.”

Johnson’s missed the Eagles’ last two games -- both losses -- with a concussion, but is expected to play Sunday when the Eagles visit the Dolphins. He had previously missed only two games to injury in his first six seasons. He was suspended twice for violating the NFL’s substance-abuse policy and missed a total of 14 games in 2014 and 2016.

This article has been corrected to show that Johnson’s new $72 million contract includes $54.595 million in guaranteed money, not $54.955.