"Absolutely. I wouldn't have come back if I didn't think we could win a championship," Girardi said. "I know there's a lot of work to be done. I know there's a lot of holes that we have to fill, and there's people leaving and people retiring, but I have faith in our organization."
Girardi piloted the Yankees to an 85-77 record this year, the third-best record in the American League East. Over six seasons at the helm of the club, Girardi has guided New York to the 2009 World Series championship and a 564-408 record, the best record of any Major League manager over that span.
"It's great to have him back," Yankees first baseman Mark Teixeira said on MLB Network. "We need to have that stability, especially in New York. He does a great job with the media, does a great job with everything that goes on around the team. We needed to have him back."
Yankees managing general partner Hal Steinbrenner and general manager Brian Cashman both offered Girardi strong votes of confidence for his performance this season, keeping an injury-depleted club alive in the postseason chase until the middle of September.
Steinbrenner and Cashman both said it was a top priority to re-sign Girardi, who previously earned $3 million per season over a three-year deal. Girardi said he and his agent, Steve Mandell, requested the fourth-year commitment.
"That was something that we brought up to them," Girardi said. "It's more stability for all of us involved in my household. It was something that we threw out at them, and they were OK with it. It's good for both of us."
The Cubs and the Nationals were among the organizations thought to have interest in Girardi for their managerial vacancies, but the Yankees did not grant permission for any club to speak with Girardi, who was under contract through Oct. 31.
Girardi said his family played an important role in his decision. After the conclusion of the regular season, Girardi gathered his wife and three children to evaluate their potential options.
The Cubs opening was a topic of discussion, and Girardi said Chicago would "always be special to me" after growing up cheering for the Cubs before playing for the club. But he also pondered a return to broadcasting, which offered a much lighter travel schedule than a big league managerial job.
"There were some things that I wanted to make sure, in my home, that people were OK with what I was still doing and that they loved what I did," Girardi said.
In the end, the consensus was that Girardi's family wanted him to continue as the manager of the Yankees.
"It's a special place to manage because of the opportunity that you have every year and the tools that they give you," Girardi said. "The history of this organization is unbelievable.
"Just to be able to put on the pinstripes as a coach, a player, a manager, whoever you are, I think it's special because of what New York has meant to Major League Baseball and what it's meant to all of us."
The biggest challenges of Girardi's managerial tenure may be ahead. The Yankees are in a transitional phase, as the "Core Four" has been reduced to just one -- team captain Derek Jeter, the last man standing after the retirements of Mariano Rivera and Andy Pettitte. (Jorge Posada retired two years ago).
Over the course of Girardi's contract, he will have to handle the final years of Jeter's career as well as the ongoing situation with Alex Rodriguez, who may miss the 2014 season and is under contract through 2017.
Outside of CC Sabathia and Ivan Nova, Girardi's rotation is a question mark at this time. His lineup outlook is also cloudy, and Steinbrenner has made little secret of his desire to reduce payroll below $189 million next season to take advantage of luxury tax incentives.
"That doesn't scare me," Girardi said. "That's part of the game, and that's part of the challenge. As a competitor, I like challenges, so I look forward to them."
The National League Manager of the Year as a rookie skipper with the Marlins in 2006, Girardi recorded his 500th win as Yankees manager May 10, in his 844th game managing the team.
That made him the fifth-fastest manager in club history to reach that number, behind Casey Stengel (790 games), Joe McCarthy (796 games), Joe Torre (833 games) and Miller Huggins (833 games).
Girardi said he was pleased by the show of support indicated by the new contract, which would give him a full decade as the Yankees' manager if he is able to complete the entire deal.
"For a manager or coach of a professional team to have an opportunity to spend 10 years in one city and watch your family grow up, it doesn't happen a lot," Girardi said. "I feel very flattered and grateful that I have this opportunity, and I really look forward to it."