"I always thought it was a decent possibility," said Ellsbury, wearing a Yankees hat during a news conference before he played his old team for the first time Thursday night. "I think of the Yankees as a top-flight organization, world class. I think of the championships, the history, the great players who play here. And when I signed over here, those were reasons why I did it."
Ellsbury went 1-for-4 with a run scored in the Yankees' 4-1 win over Boston.
The Yankees gave Ellsbury a seven-year, $153 million contract, far exceeding any offer the Red Sox indicated they would make to retain the center fielder. Upon agreeing to the deal, Derek Jeter called Ellsbury and told him what is like as a Yankee.
"Derek called me and said, 'You are going to enjoy it here, it is a first-class organization,'" Ellsbury said. "'It is a special place to play.' From then on, I had the highest expectations and they've met them and exceeded them."
Ellsbury has started strong for the Yankees, hitting .351 and transitioning from the leadoff spot to the No. 3 hole in the lineup after Mark Teixeira landed on the disabled list.
"I'm excited to play," Ellsbury, 30, said prior to facing Boston. "I spent nine years in the organization, seven years in the big leagues, roughly a third of my life. I left it all on the field for the Red Sox."
On Thursday, Ellsbury faced his first roommate, Clay Buchholz, from Class A nearly a decade ago.
"I've never faced Buck before," Ellsbury said. "I came up with him. He was my first roommate in Lowell. A lot of great memories, relationships. He'll be a friend of mine for life."
Ellbury emphasized how much he enjoyed playing in Boston, highlighted by the two World Series titles the Red Sox won. He expected to receive his 2013 World Series ring Thursday or Friday.
He did not make it to the White House with his former teammates earlier this month, but he did catch some of the festivities.
"The one thing I did catch was David [Ortiz] at the White House with the president," Ellsbury said, referring to Ortiz's selfie with President Barack Obama. "I think everyone saw that. That was pretty funny."
In 1½ weeks, Ellsbury will return to Fenway Park for the first time when the Yankees visit the Red Sox.
The passion that his defection has caused is one of the reasons Ellsbury said he enjoys the rivalry so much.
"That's the reason I love this rivalry, the passion that the fans have," Ellsbury said of what he expects upon his return. "I haven't thought about it too much because whatever reception I receive will be out of my hands."