George Kittle has agreed a five-year contract extension with the San Francisco 49ers worth $75million, according to reports.
NFL Network's Ian Rapoport says Kittle is to become comfortably the NFL's best-paid tight end, while he will also receive an $18m signing bonus.
More than half of the deal is said to be made up of guarantees.
The 26-year-old had been set to be a free agent at the end of the 2020 season.
Kittle, taken fifth overall in the 2017 draft, played a starring role in the previous campaign as the 49ers reached the Super Bowl before losing to the Kansas City Chiefs.
The two-time Pro Bowler played 14 games in the 2019 regular season and had 85 receptions for 1,053 yards and five touchdowns.
Over a three-year NFL career, Kittle has played 45 games and has 216 receptions for 2,945 yards and 12 touchdowns.
Kittle's new contract surpasses Rob Gronkowski's six-year, $54m pact with the New England Patriots in 2012 for the largest ever for a tight end.
It also exceeds the record average annual value at the position, which saw Austin Hooper sign a four-year, $44m deal with the Cleveland Browns earlier in 2020.