Updated

Police say up to 2 million Giants fans could turn out to cheer the World Series champions in a downtown San Francisco parade featuring double-decker buses carrying the players and floats of the Golden Gate Bridge.

One of the floats will be a panda in honor of third-baseman Pablo Sandoval, whom teammates have nicknamed "Kung Fu Panda."

Rain will likely pelt the parade, which begins at Market and Steuart streets at noon and then heads to San Francisco City Hall and Civic Center Plaza, where Mayor Ed Lee will honor the team with a giant onstage ceremony.

The 3-2 victory Wednesday against the Kansas City Royals was the Giants' third World Series championship in five years. Players, including the series' Most Valuable Player, 25-year-old pitcher Madison Bumgarner, will ride on double-decker buses. The streets are expected to be awash in orange and black.

Parade efforts were long underway before Sandoval snagged the final fly ball and dropped on his back on the field in victory.

"Unlike most parades where we have weeks and months to plan, this all kind of came down the pipes over the course of days. So we're doing about a month's work in about a week," The Parade Guys' Stephanie Mufson told ABC7 News. The San Francisco company started building the floats earlier this week, because waiting for the final out would have cut it too close.

The parade is free and open to the public.

Police Chief Greg Suhr said the number of officers on the streets Friday will be at least 20 percent higher, with police dogs helping with security.

"We will prepare for any inevitability, but we are hoping for the best," Suhr said Thursday, adding that crowds are expected to be massive. "I wouldn't be surprised if there were 2 million people in San Francisco (for the event) Friday."

Suhr said he hopes the parade will bring out the best in fans.

Following the win Wednesday, fans initially gathered in the streets, uncorking champagne, dancing and hugging strangers. But the celebration quickly turned raucous and violent, as about 100 revelers vandalized police cars and businesses and pelted officers with bottles.

Forty people were arrested for public drunkenness, assaults and outstanding warrants. Nine police cars were damaged, and three officers went to the hospital with injuries, Suhr said. Two people were shot and two people were stabbed in separate incidents. All of the victims are expected to live.