Papelbon donned a kilt and danced his trademark Irish jig to the roars of tens of thousands of fans today as the city celebrated Boston's second World Series title in four years with a three-mile-long rolling rally from Fenway Park to City Hall Plaza.

"The fans connect to Papelbon because he cuts loose, he's passionate," said Red Sox fan Brian McCarty, who was carrying "Mobile Papelbon," a giant cardboard likeness with its legs on hinges.

Players and their families boarded 20 amphibious, World War II-era duck boats outside the stadium for a journey through the city. Manny Ramirez grabbed a microphone and yelled to fans along the route. "You guys are No. 1." "There's a party at my house tonight." "We did it for you guys." "We're gonna do it again next year." "You guys are the best fans in the whole world."

Fans showed their love back for the team, chanting "MVP" to Mike Lowell and waving signs with wedding proposals to rookie Jacoby Ellsbury.

The two-hour parade paused three times for Papelbon to dance on a flatbed truck, accompanied by the Dropkick Murphys, a Boston-based punk rock band with heavy Irish folk music influence.

Before the parade, the band presented Papelbon with his own kilt plus one for ace Josh Beckett and general manager Theo Epstein, who had promised to dance with him. They also made a kilt for slugger David Ortiz, whom they hoped to coax into the jig.

At the first two stops at Copley Plaza and Boston Common, Papelbon danced alone, wearing jeans, a red championship T-shirt and dark sunglasses and waving a large cigar in his hand. Along the route, he played air guitar on a broom — a reference to Boston's sweep of the Colorado Rockies.

But he saved his best dancing — and wardrobe change, putting the kilt over his jeans — for the largest crowd which packed City Hall Plaza, the end of the parade. He was joined by relievers Hideki Okajima and Mike Timlin, who earlier had tied the bullpen mascot, a stuffed parrot, onto one of the speakers on the Dropkick Murphys' flatbed. On another boat, six members of Boston's bullpen recreated their postseason jam sessions.

Ortiz and Epstein never got the chance to don their kilts, as their duck boats continued on the route.

The caravan of duck boats followed a similar route to the rolling celebration staged after the Red Sox broke an 86-year World Series drought in 2004 by sweeping the St. Louis Cardinals. The Red Sox completed a sweep of the Rockies on Sunday with a 4-3 win in Denver.

Mark Rinaldi, a student at Harvard, said he attended the 2004 parade and "I never thought I'd be able to do it again in my lifetime. To do it twice is pretty incredible."

Most of the players and manager Terry Francona wore bright red hooded championship sweat shirts. Some, including first baseman Kevin Youkilis and Timlin, wore T-shirts that said "We did it AGAIN." Many of the players took photos or video recordings of the fans along the way.

Owner John Henry, wearing an argyle gray sweater, tapped his hand on his heart in thanks as he waved to fans from a lead boat, which also carried the new World Series trophy.

Fans decked out in Red Sox gear lined the route, holding signs and cheering for the team. Some couldn't resist a shot at the archrival New York Yankees and former Red Sox star Johnny Damon, who defected to New York after the 2004 championship.

"Johnny Damon is home changing diapers," read one sign. "This is better."

Along the way, fans yelled to team management "Re-sign Lowell."

Ramirez agreed, telling a City Hall crowd, "Forget about A-Rod, we've got Mike Lowell in the house."

One fan held a sign also referring to Alex Rodriguez, the Yankees third baseman who this week opted out of his contract with New York: "A-Rod: Mr. April, Miss October."

There were some indications Boston fans might even be getting picky about their championships, with 2004 and 2007 coming when the Sox were on the road.

Ortiz said a fan asked him when the team was going to win a World Series at Fenway.

"I told him, 'Dude, it doesn't matter where you win it, as long as you win it,"' Ortiz said.

Red Sox president Larry Lucchino said before the parade that he could not choose which Series win he liked better.

"They're two flavors of ice cream — they both taste good," he said. "You can't choose among them. I think the next one is going to taste good, too."

Mayor Thomas Menino acknowledged having the celebration on a week day would inconvenience some businesses and keep school children away, but said players were eager to get home to their families and begin their vacation. This year's parade had one significant difference from the 2004 parade: it did not proceed into the Charles River. Menino said that decision was made by the team.

Before the parade, Menino stumbled on the stairs at Fenway while carrying the 2004 World Series trophy and injured his knee. A spokeswoman said he hyperextended his knee, but was fine.

Menino also said a "rolling rally" was easier for city officials to manage, because it spread out the crowds. He estimated security would cost $500,000.

Police refused to give a crowd estimate. People were lined up along the three-mile route, dozens deep at some points.

AP reporters Matt Pitta, Ken Maguire and Jimmy Golen contributed to this report.