Can you guess the state sport of Massachusetts?

It was a moment of triumph for fourth-graders from the Joseph P. Mulready School in Hudson. Dressed in oversized Boston Celtic s jerseys, they cheered as Governor Mitt Romney, with a stroke of his pen, pronounced basketball the official sport of Massachusetts.

They had proposed the bill for the designation, written to legislators, and testified at the State House. Now, their victory secured, it was time for cake, thick slices of which they devoured in the State House pressroom.

But out on the streets of Boston, despite a solid defense from Romney and other hoop advocates, news that basketball had become the state's official sport triggered disbelief.

Yes, sports fans conceded, James Naismith invented basketball in Springfield in 1891, when he nailed a peach basket to a gymnasium wall. And yes, the Boston Celtics have won 16 championships, more than any other team. But their last championship was in 1986, when Larry was becoming legend.

Since then, the Red Sox have broken the baseball team's storied curse, bringing euphoria to millions by winning their first World Series in 86 years. The New England Patriots have played in five Super Bowls and won three.

Fans said that naming basketball the official sport seems out of step with the hearts and minds of the city's diehard sports fans.

``Fenway is so big here in Boston, I can't see making a team like the Celtics and basketball the official sport," said Vincent Colafella, 23, who was outside Caffé Graffiti in the North End yesterday, wearing a blue Italian soccer jersey. ``That makes no sense.

``I would love it if it were soccer," he said, ``but we're in Boston, and it's the Red Sox."

Make that Red Sox Nation.

Jerry Moscato, 60, who also was outside the café, scoffed at the notion that basketball reigns in Massachusetts.

``Football first, Red Sox second, and the Celtics and the Bruins are down at the bottom, 'cause they can't win," Moscato said. ``It used to be a hockey town; no more. It used to be a basketball town, when the Celtics were good, [with] Russell, Cousy, in the old days."

Gabriel Nunez, 53, who was outside the Cask 'n Flagon bar near Fenway Park yesterday, said it seemed hard to believe that the government had, in fact, decreed basketball the official state sport.

``Basketball? I don't hear much about basketball anymore," he said. ``Now, every time you look around, somebody's talking about the Red Sox."

Romney, however, strongly defended basketball, saying it has more than century-old roots in Massachusetts. ``I love the Sox, and we love the Patriots and all our professional teams, but this was the game that was invented here, and our linkage to history is what makes it appropriate for this to be the state's official sport," he said at the signing.

He added that basketball, which was invented to help keep students at the Young Men's Christian Association Training School fit in winter, still ``allows young people to get exercise in the winter, which can be pretty darn long."

``It's not about the pros alone; it's also about all the young people throughout the Commonwealth who play this sport," Romney said.

Not surprisingly, Celtics CEO Wyc Grousbeck applauded the signing of the bill

``Massachusetts is known worldwide as the birthplace of basketball," Grousbeck said.

Celtic legend Bob Cousy, who attended the ceremony with former Celtic Jo Jo White, said he also was delighted. Cousy won six championships with the Celtics.

``We're happy that we're acknowledging that basketball is number one, because we've obviously felt that way for a long time," Cousy said.

``Jo Jo and I are part of a great Celtic tradition," he said, ``and I still take great, great pride in playing a small role in those six championships."

Basketball, regardless of public opinion, now joins a pantheon of other official state items, many of them far more obscure than roundball. The mayflower is the official state flower; the black-capped chickadee, the official state bird, cranberry juice, the official beverage, and Dighton Rock, the official state explorer rock. (Yes, Plymouth Rock didn't rank.)

And while fans in Boston passionately defended either baseball or football as the top sport in the state, Moscato, in the North End, said allegiances could switch. Just wait till next year.

``You want to know who's number one in Massachusetts?" Moscato said. ``Whoever's winning, that's who."