It's a small shot at the Yankees and their fans, but it's one that will be remembered come May 12 when the Mets visit Yankee Stadium.
Here's a look at some of his comments from the press conference, including his joke concerning the Yankees:
Of course, many New Yorkers didn't take too kindly to that:
It's understandable some Yankees' fans would be angry. After all, he was a player the Yankees thought would help them win another World Series after posting 30 home runs and 20 stolen bases in 2009 with the Detroit Tigers.
However, the Yankees never made it past the ALCS. With Alex Rodriguez, Mark Teixeira and Robinson Cano, a World Series was all but guaranteed with the center fielder. Once in pinstripes, Granderson continued to show his power, although his average suffered.
In his four years in pinstripes, Granderson batted .245, but had 115 home runs and 307 RBI. Over the last three years, Granderson has ranked among the best outfielders in terms of power, according to ESPN's John Buccigross:
Granderson may have never brought the Yankees a World Series title, but he definitely held his own in the Bronx. In fact, outside of average, he had more home runs than Teixeira (99) and Rodriguez (71), and only two less than Cano (117) over a four-year period.
Now he moves to another borough and another league.
For fans who are angry about the comment, just chalk it up to him trying to please his new home fans. He no longer needs to concern himself with what Yankee fans think of him.
Plus, it's not like he went to the Boston Red Sox. New York fans would be calling Granderson a traitor if he did what Jacoby Ellsbury did to the Red Sox.
Although the Mets and Yankees are rivals in a sense, they still play in two different leagues. They only play four times in the regular season. They compete for the same fans, but that's about it.
Granderson's comment added a little flair to the offseason, but in the end, it will be forgotten until the two games at Yankee Stadium in May. After that, nobody will remember it at all.