Tom Brady has signed a three-year extension with the New England Patriots that will run through the 2017 season.

Brady will be 40 in 2017.

The three-year extension is worth $27 million, which represents a significant discount for a quarterback of Brady's caliber.

The extension will pay Brady a $3 milion signing bonus immediately, in addition to salaries of $7 million in 2015, $8 million in 2016 and $9 million in 2017. 

The cap savings for the Patriots is significant.