The forecast calls for a 90 percent chance of rain in Philadelphia on Saturday night, when Game 3 of the World Series is scheduled to be played at Citizens Bank Park.

If the game's postponed, fans with tickets for Games 3, 4 or 5 would have to adjust their schedules to attend on a different day.

Getting a few hours of rain-free skies doesn't seem likely Saturday evening, a National Weather Service meteorologist said this morning.

"No, it's a pretty widespread area," said Bill Christ of the service's Mount Holly office.

"It's supposed to come in late Saturday morning and last all day into Saturday evening. Rain can be heavy at times," he said.

Thunderstorms are even possible.

The teams play Game 2 tonight, then have tomorrow off. The Phillies won, 3-2, in the Series opener last night.

If there's a Saturday rainout, tickets for Game 3 would be honored on Sunday instead, Game 4 on Monday, and Game 5 on Tuesday, which was to be an off day for the teams, according to baseball spokesman Pat Courtney.

The rain might linger into Sunday morning, but should be heading out by afternoon, Christ said.

Fans with Game 3 tickets could be doubly inconvenienced. They might begin traveling to the ballpark, or even see play begin, before being told to come back the following night.

Air travelers might have to scramble to change their flights.

Fans should note, however, that forecasts have been wrong before.

A lingering nor'easter with periods of heavy rain was expected the last weekend of the season, especially threatening the night game of Friday, Sept. 26.

That game was played without a rain delay. The following afternoon, a 4-3 win clinched the division title.

A rainout might mean that Phillies ace Cole Hamels could wind up pitching Game 4 instead of Game 5 on Monday. That wouldn't change (contrary to an earlier version of this article) his availability as a starter for a decisive Game 7 - unless a second rainout postpones that matchup past Thursday.

Phillies pitching coach Rich Dubee and Rays manager Joe Maddon declined to speculate about possible adjustments to their teams' rotations.

"It's too early to tell," Dubee said.

"We'll have to wait and find out," Maddon said.

Sports talker Al Morganti on WIP (610 AM) this morning speculated that Major League Baseball might welcome the rainout and announce a postponement early, because Saturday night is the worst night for TV ratings and the big Penn State-Ohio State college football game could cut into the audience.

Contact staff writer Peter Mucha at 215-854-4342 or pmucha@phillynews.com.

The Associated Press contributed to this report.