Ellsbury was selected by the Red Sox in the first round of the First-Year Player Draft in 2005.
By 2007, he went from September callup to starter on a championship team.
Ellsbury set a new team record for stolen bases with the Red Sox with 70 in 2009. That same season, he had a memorable straight steal of home at Fenway Park against Andy Pettitte and the Yankees.
And in what proved to be his last season in Boston, Ellsbury again was part of a World Series-winning team.
"That in itself is a career," Ellsbury said. "I feel very fortunate. A lot of players don't even get to the postseason, let alone a World Series. To win it twice, I feel very fortunate."
Now Ellsbury hopes to join another exclusive club that is inhabited by Babe Ruth, Johnny Damon and a few others. But there aren't many players who get to experience winning a World Series for both the Red Sox and the Yankees.
"Like I said, I'm excited to hopefully do it in New York. That'd be really special," Ellsbury said. "The picture of [Derek] Jeter holding up the trophy, I feel like I see that picture everywhere. That'd be very special to win it here in New York."
Yet he won't forget about the close ties he made with the Red Sox. Dustin Pedroia and Ellsbury have long been good friends. That won't change just because Ellsbury is changing uniforms.
"I've always been in constant relationships with them," said Ellsbury. "I went out to eat with Dustin yesterday. You build relationships through baseball that you have regardless of whatever jersey those guys have on. That the type of relationship I have with the guys in that clubhouse, but we know that when it comes down to playing, we're all competitive, so it'll be fun playing against them. They wished me the best, they understood. It was nice to hear that from them."
Ellsbury will next hear from Red Sox fans on April 22, when the Yankees make their first visit of the 2014 season to Fenway Park.
"I'm not sure [what the reception will be]," Ellsbury said. "I guess how I look at it is, like I've mentioned numerous times, just the memories I have there when I was there. Fans cheered me. They cheered me on. The fans were great to me, and I was always thinking of winning the championships, so I guess we'll see. I definitely appreciate them and my time there."