The MLB Network celebrates the one-year anniversary of its launch on New Year’s Day, and its first season has been a remarkable success.

It began with the largest network debut in cable television history, launching in 50 million homes. It ends the year as a new acquaintance that won’t soon be forgotten, a baseball paradise for passionate fans that features a balance of breaking news, well-considered analysis, and irresistible nostalgia.

“It’s really been everything we hoped it would be,’’ said Harold Reynolds, the former major league second baseman and ESPN analyst who, along with former NESN host and reporter Hazel Mae, was among the network’s initial on-air hires. “But to be honest, I don’t think it surprises anyone who works here, who has been here from what was basically the start.

“The biggest thing about when I was approached to come here is that it was quickly obvious that Tony [MLB Network president and chief executive officer Tony Pettiti] had this clear vision of what this was going to be, and he was going to do all he could and hire the right people to help realize that vision. It was very easy to become excited about the possibilities and have high expectations before we even got started.’’

The vision was apparent from the network’s first moments on the air, appropriately enough a full replay of one of the sport’s signature performances, Don Larsen’s perfect game in the 1956 World Series. From its inaugural days, the network has featured a lineup of fresh and fascinating programs, including “Prime 9,’’ a list show of various bests and worsts; “Baseball Seasons,’’ an hourlong look at individual years in baseball history; “Studio 42 With Bob Costas,’’ an interview show whose accomplished host ratcheted up the credibility factor; and its signature in-season program, “MLB Tonight,’’ which provides live look-ins and instant analysis.

The merits of “MLB Tonight’’ were proven July 10 when a national audience was treated to the final three innings of Giants pitcher Jonathan Sanchez’s no-hitter. But the network’s bonafides were proved beyond a doubt little more than a month into their existence. When Sports Illustrated reporter Selena Roberts had the stunning scoop in early February that Yankees superstar Alex Rodriguez tested positive for steroids, eyes turned toward the fledgling network. Would it treat it as a news story? Or would it brush it aside, thus proving to be a house organ for Bud Selig and Major League Baseball?

Looking back, Reynolds recognizes it as the network’s pivotal moment.

“We covered that story as thoroughly and fairly as possible, and there’s no doubt it put us on the map,’’ Reynolds said. “We had Jon Heyman and Tom Verducci providing news and doing the hard reporting. We had Costas interviewing Selena Roberts in the studio, and of course, you know Bob, he didn’t lob softballs. He asked all the hard questions. We covered that story like the huge news that it was, and it was a real indication that this was going to be different, that we had the reporting chops. It told people that we weren’t beholden to anyone, that we would face the tough issues.’’

Of course, a major part of the network’s appeal is that it is not just about the tough issues. There’s a deliberate daily emphasis on sharing in the joy, history, and delightful minutiae of baseball, something that will only be enhanced with the recent hiring of Peter Gammons. Yesterday afternoon’s programming lineup was typically diverse and entertaining: included were an hourlong look at the surprisingly compelling 1984 Padres, a debate-spurring “Prime 9’’ episode on the nine best catchers of all time, and a replay of the Mariners’ win over the Yankees in Game 5 of the 1995 ALDS, which was briefly interrupted when Mae cut in to report that the Orioles had signed free agents Mike Gonzalez and Garrett Atkins.

The on-air staff’s uncommon chemistry was evident from the beginning. Mae, who remains popular in New England since her four-year run at NESN coincided with one of the most memorable stretches in Red Sox history, says she knows why.

“It’s the common goal,’’ said Mae. “Everyone in the ensemble we have here loves baseball and realizes how fortunate we are to do what we do. So the camaraderie happens naturally.’’