After 21 seasons in the NBA, Dirk Nowitzki finally announced his retirement from the NBA this season. It was an incredible season for Nowitzki where he was honored at almost every single NBA arena he went to. The Mavericks legend waited until the last week of the season to make his retirement official, which meant there was always a chance that he could have returned next season. With fans in Dallas sad to see him go, Dirk made sure he did everything he could to honor the fans and make sure they know they are appreciated.

According to Sneaker News, Nowitzki took out a full-page ad in the Dallas News which paid homage to Mavs fans.

Dallas,

Twenty-one seasons.

One team. My home.

No stat, no record, no award in this game means more to me.

We won an NBA Championship together.

From the moment I arrived in Dallas riding on this amazing roller coaster, you lifted me, supported me, pushed me to work harder.

So many memories. So many stories. They are not only mine. They are ours.

This is not goodbye.

This is THANK YOU Mavs fans, from the bottom of my heart, for taking in a kid from Wurzburg and making me one of your own.

I will miss playing, but I can't wait to start the next chapter with you.

Forever and grateful, forever yours, and forever a Dallas Maverick.

-- Dirk Nowitzki

Unfortunately for Dirk, his final season didn't end the way he would have liked, as the team failed to make the playoffs and finished 14th in the Western Conference.