Ngata wrote in an Instagram post:
"Just a man standing on top of the world with a heart full of gratitude. Thank you Lord for letting me play the game I love for 13 unforgettable years. I'm retiring on top. I might be finished playing football, but I'm holding tight to the friendships, memories and wisdom I've gained along the way. 'Nobody who ever gave his best regretted it.'
"Walking away with no regrets, just peace in knowing I gave it my all and had a helluva lot of fun doing it."
Ngata, 35, spent his first nine seasons with the Baltimore Ravens and was one of the fiercest run-stuffing defensive tackles in football. He notched all his Pro Bowl and All-Pro honors, including three second-team All-Pro nods, in Baltimore. He then played three seasons with the Detroit Lions before finishing his career with the Philadelphia Eagles in 2018.
The Ravens won Super Bowl XLVII thanks to a defense anchored in the middle by Ngata and a brilliant run by quarterback Joe Flacco.
Ngata's last few seasons were hampered by injuries. He missed at least two games because of injury in each of his last four seasons and 19 games total during that time. That hindered his ability to be as effective as he would have in years past, but Ngata was still a solid run stuffer last season as part of the Eagles' line rotation.