Andrew Luck has signed with the Indianapolis Colts through 2021

The Indianapolis Colts have signed star quarterback Andrew Luck to a new six-year contract, which keeps him with the team through 2021.

The 26-year-old. who the Colts selected first overall in the 2012 draft, was entering the final year of his rookie contract.

The deal is worth $140m (£104m), the richest in NFL history. The biggest prior deal in NFL history saw Green Bay quarterback Aaron Rodgers ink a five-year contract for $110 million in 2013.

Colts owner Jim Irsay tweeted: "Andrew has signed through 2021. $140 Million over 6 Years... Biggest Contract in NFL History... Congrats to #12!!!"

Seattle Seahawks quarterback Russell Wilson signed a four-year deal last year worth $87.6m that featured $60m guaranteed, while Luck reportedly will have $87m guaranteed, or $22m more assured than the old marks to Eli Manning of the New York Giants and fellow quarterback Philip Rivers of San Diego.

Luck said: "I am thrilled and excited to continue with this great organisation. I am thankful to the Irsay family and Mr Irsay for providing me with this great opportunity and the trust that they've shown in me. I can't wait for this season to start.

"I truly appreciate Mr Irsay and the Irsay family for the level of commitment and trust they've shown in me. I've loved being a Colt and I'll continue to love being a Colt. It won't change my process or preparation in any way.

"It's all about winning and we understand that in this building. It's a great winning franchise that knows how to win. We need to get back to the play-offs and give ourselves a chance to get to the Super Bowl."

Andrew Luck has made three Pro Bowls in his four seasons with the Colts

Luck justified the Colts' decision to move on from team legend Peyton Manning by leading the team to the play-offs and being named to the Pro Bowl in each of his first three seasons in the league.

The former Stanford Cardinal has the fourth-most passing yards (14,838) by any quarterback in his first four seasons in NFL history and became the fourth-fastest quarterback in history to throw for 100 touchdowns by achieving the feat in his 55th game.

He endured the worst season of his career in 2015 as he missed nine games through injury and the Colts missed the play-offs.

Aaron Rodgers was previously the NFL's highest-paid quarterback after signing a five-year, $110m deal with the Green Bay Packers in 2013.

Luck was scheduled to make $16.155m this season, the fifth-year option on his rookie contract.