Tom Brady and Peyton Manning represent the NFL’s best rivalry in the last 15 years, and there’s a lot of respect between them despite their fierce battles on the field.

Manning will announce his retirement Monday, and the New England Patriots quarterback wrote a message on his Facebook page to congratulate his rival on a tremendous career.

Congratulations Peyton, on an incredible career. You changed the game forever and made everyone around you better. It's been an honor.

Posted by Tom Brady on Sunday, March 6, 2016

Brady and Manning met on an almost-annual basis for most of their careers. They also played five times in the playoffs. Brady won the first two playoff matchups en route to Super Bowl wins in 2003 and 2004, while Manning won the last three, including the most recent AFC Championship Game.

Thumbnail photo via Kevin Jairaj/USA TODAY Sports Images