Flanked by general manager Theo Epstein and owner John Henry, the soft-spoken Gonzalez donned a numberless home Red Sox jersey (he'll have to duke it out with old friend Mike Cameron if he wants the No. 23 he wore in San Diego) and spoke of growing up rooting for Boston from afar with a desire to one day play in Fenway.
"I had five incredible years in San Diego, where I grew up trying to play in the major leagues and be a Padre," Gonzalez said. "But my second dream was to be a Red Sox and so I'm very excited ... to start this new phase. I look forward to a lot of world championships."
Gonzalez later tossed in a reference about being ready to "beat the Yanks," the most surefire way to endear himself to the region. Another way is that over seven seasons, Gonzalez hit .284 and averaged 32 home runs and 99 RBIs.
The Red Sox will ship minor leaguers -- outfielder Reymond Fuentes, right-handed pitcher Casey Kelly and first baseman Anthony Rizzo -- and a player to be named later to San Diego in exchange for Gonzalez.
"This is one of the best hitters in baseball," Red Sox manager Terry Francona said from Orlando in an interview on Boston sports radio station WEEI. "This is a big move for us. We're getting a middle-of-the-order bat, a guy that's won a couple of Gold Gloves. He's still young. This is exciting. We gave up some good players to get him, but that's the only way you can get a guy of his caliber."
Yankees general manager Brian Cashman said the addition of Gonzalez makes the Red Sox "a great team."
"He's a heck of a hitter. That's a huge addition for Boston," Cashman said. "They just obviously improved themselves in a significant way. He's one of the premier players in that position in the game."
The Padres admitted that they couldn't afford to re-sign Gonzalez after his contract expires at the end of the season. The Red Sox had been trying to negotiate an extension but went ahead with the deal without a long-term contract in place. Epstein said he's "confident" something will be worked out.
"There was a lot of good faith that developed over the course of the negotiations and both sides have an understanding of what it will take, when the time is right," Epstein said. "We got close to a deal, but in the end the [48-hour] window [to negotiate] lapsed and we didn't have a deal. We decided to go forward with the trade anyway, as a demonstration of the good faith that developed. Had we not gotten to know Adrian and his wife [Betsy] and what they're all about over the course of the weekend, we probably wouldn't have had that comfort.
We think that he's such a good fit -- Adrian wants to be a Red Sox -- and we want him to be a Red Sox for a long time."
Gonzalez is a three-time All-Star who hit .298 with 31 homers and 101 RBIs last season. In five seasons with San Diego, Gonzalez has 161 homers and 501 RBIs. Including parts of two seasons with Texas, he has 168 homers and 525 RBIs.
"He's one of very best hitters in the game, left-handed hitter, tremendous ability to control the strike zone, hit for power, power to all fields," Epstein said. "His natural stroke is to the opposite field, which is a great fit for our ballpark. He hits the ball the other way, so he'll be using the wall, and we think he'll wear the wall out going from [pitcher-friendly] Petco [Park] to Fenway Park."
Epstein joked Gonzalez would need to work on his speed with all those doubles he stands to register off the wall.
Gonzalez added: "My first fly ball to left that would have been an out at Petco, I'm looking forward to getting to second base [at Fenway]."
San Diego gets some of Boston's top prospects. Padres general manager Jed Hoyer was familiar with the Red Sox's farm system since he worked under Epstein in Boston for years.
Saying that Epstein is his good friend and they talk often, Hoyer expressed regret that the Padres had to lose Gonzalez.
"Adrian is a superstar player, and I certainly wish we could keep him in San Diego long-term but we can't," Hoyer said. "I think he's going to be unbelievable at Fenway Park. He hit so many fly balls the other way, and so many times they just died before the warning track at Petco Park. He's going to be a monster at Fenway Park. They've got themselves a great player, a player we certainly wish we could have kept. Red Sox fans will certainly enjoy watching him play for a long time."
Epstein took advantage of being in a bigger market but didn't think he got Gonzalez for nothing.
"It wasn't a situation where either side was looking to pull a fastball on the other," Epstein said. "This trade was all known commodities. We know Adrian really well, we know that he's of one of the best players in the game; Jed knows our system well and got three great prospects. This is a win-win-win situation."
Francona said he could tell that Epstein thought this deal was critical.
"I could tell that Theo was really digging his heels in on this one," Francona said. "And I'm glad he did because when he feels that strongly it's got a chance to really be good for us."
The Red Sox hope they have landed their long-term solution to losing out on free agent Mark Teixeira two seasons ago. He agreed to an eight-year, $180 million deal with the Yankees, and it remains to be seen how close to that financial neighborhood Gonzalez ends up.
One baseball source suggested to ESPNBoston.com that eventually a compromise in the seven-year, $22 million-per-season range might get the deal done. The Red Sox might actually benefit from a luxury-tax standpoint by holding off on the deal until after Opening Day, when it won't count against the team's payroll for tax purposes.
Chris Forsberg is a reporter for ESPNBoston.com. Information from The Associated Press was used in this report.