That Mills, bench coach for the entirety of Terry Francona’s career with the Red Sox, was named yesterday as the manager of the Astros has much to do with his experience in Boston, a fact that Houston ownership and management repeatedly emphasized at his introductory press conference in Houston.

“Therein lies the separator - 45 postseason games, two World Series,’’ Wade said in introducing the 52-year-old Mills. “He’s got more World Series rings than anybody in this room. Those are great separators.’’

The Houston GM was a bit more lighthearted in letting Francona know that his bench coach had been taken from him. Wade - who fired Francona when he was with the Phillies - called his former employee with the news, but first tried to convince the Sox manager that Mills hadn’t gotten the job. And when Francona did finally find out the truth, there was far more excitement than regret - even as he loses one of his close friends and advisers, a man he has known since they were road roommates in college.

“He’s wanted this,’’ Francona said. “I’m so proud, not just of him, but for him. He’s not going to shortchange anybody on effort. He embodies so much of what’s good in our game. I’m so happy for him. This meant a lot to him, as it should. I’m so thrilled for him. How much we’re going to miss him, sure, but it’s so far outweighed by happiness.’’

Francona has made no secret of his desire to see Mills get a chance to lead a team, a feeling he was clear about when Mills finally got an interview with the Mariners last offseason, and again when he interviewed with Houston this year.

“ ‘Attack’ is a good word,’’ said Francona, describing how Mills will approach his new role. “He’s got a lot of skills that are going to help make him a successful manager. He understands communication. He respects the players.

“I think he’ll make the players be accountable, all the things we’ve talked about for six years in Boston. He’s a smart baseball person and he’s a very good person. That’s a pretty good combination.’’

Now the Red Sox will be faced with replacing a man Francona relied upon heavily. Mills was responsible for much that occurred during spring training, along with his in-season tasks, and was responsible for one of the more notable moments in the 2007 World Series victory - when Jonathan Papelbon picked off Matt Holliday at first base.

Asked if he might turn to an internal candidate as his next bench coach, Francona said, “I hope so. I really hope so. I think that’s something that’s important. I’ve been here long enough now that it’s something that definitely needs to be considered. That doesn’t mean that anybody’s a lock to get a job.’’

Francona said he had talked to general manager Theo Epstein, and that they would take a step back before making a move. As Francona said, “Think we’ll let it slow down. I think we’re situated pretty well.’’

Third base coach DeMarlo Hale, who also interviewed last year to be manager of the Mariners, could be among those considered for the position, as could other members of the major league staff. Bullpen coach Gary Tuck has been a bench coach, and John Farrell, who has turned down multiple interview opportunities to be a manager, could be a candidate. Minor league field coordinator Rob Leary could be ready for a promotion.

Before Mills stood at the podium posing for cameras and holding up his new jersey, he answered about half a dozen questions from the media in Houston. He started, though, with a thank you. He thanked John Henry and Tom Werner and Larry Lucchino and Epstein and Francona, all those who had been with him for six years in Boston.

“The one thing I’m going to bring in is a freshness, being with a champion, and bring that freshness in,’’ Mills said. “It’s a fresh voice, a new voice. Playing the game right is always said, but we want to play winning baseball. We want to come together, work together, in becoming a winning franchise, a winning organization.’’

Just like the one he left.

“It’ll be different,’’ Francona said of life without Mills. “Making no bones about it. I’ve probably taken Millsy for granted.

“We’ve been friends for 30 years. You can’t replace that. He got his chance to do his own thing. We’re so happy for him, but replacing him won’t be easy, that’s a given.’’