"Obviously, when you're a professional athlete, it's tough to close a book on something that you love to do," Gonzalez, who turns 42 on Thursday, said at a news conference before the Diamondbacks played Houston. "But at the same time, it's a new beginning for myself, for my family."
In his new role, Gonzalez will assist Diamondbacks president and CEO Derrick Hall and other departments throughout the organization.
"Whatever they ask me to do, I'm open and willing to do that," Gonzalez said. "I have a strong passion for this game."
The most popular player in the franchise's 12-year history, "Gonzo" will always be remembered for hitting the winning bloop single off New York Yankees closer Mariano Rivera in Game 7 of the 2001 World Series -- still Arizona's only major sports championship.
"My biggest thrill in my career was winning a world championship," Gonzalez said. "I had one shot at it in my 18 years, and we ended up winning a championship here in Arizona."
Gonzalez spent his best eight years with Arizona, arriving in 1999, the franchise's second season. But he had a bitter parting with the Diamondbacks, who informed him late in 2006 that they would not pick up his $10 million contract option for 2007.
Gonzalez's final game as a Diamondback, on Oct. 1, 2006, drew 48,972 -- at the time the largest regular-season crowd in team history.
The hard feelings apparently are gone. Gonzalez, who lives in the Phoenix area, said he still roots hard for the Diamondbacks.
"My wife could tell you, it kills me every time the D-backs lose," Gonzalez said of a team that entered Saturday two games above .500 since he left.
Gonzalez was given a rousing welcome before the Diamondbacks played the Astros on Saturday night. The Chase Field crowd stood and applauded as Gonzalez received the key to the ballpark from Hall and managing general partner Ken Kendrick.
A five-time All-Star, Gonzalez batted .283 with 354 homers and 1,439 RBIs in 19 seasons with Houston, the Chicago Cubs, Detroit, Arizona, the Los Angeles Dodgers and Florida. He last played in 2008, with the Marlins.
Gonzalez led the NL with 206 hits in 1999.
Known for hitting liners, Gonzalez had an unexpected power surge in 2001, hitting 57 homers, 26 more than his previous high. He hit 28 homers the following season, and his totals declined in five of his final seven seasons.