"Along with the NFL office and the Jets, we have closely monitored the hurricane and the forecast and its potential impact on our area for the past several days," Giants president and CEO John Mara said in a statement released Friday night.
"After conferring with (New Jersey) Governor (Chris) Christie, (Jets owner) Woody Johnson and (NFL) Commissioner (Roger) Goodell, we have determined the best course of action for the safety and well-being of all is to move the game to Monday night."
Hurricane Irene was on track to reach the New York area by Sunday.
New York City planned to shut down the entire mass transit system by noon on Saturday.
The game was originally scheduled for 7 p.m. Saturday and later rescheduled for 2 p.m. The Giants kept a close eye on the forecast on Thursday and Friday and stayed in touch with the NFL league office prior to the decision.
The afternoon game will be held on Sept. 8, previously an off day for both teams. The time of that game will be announced at a later time.
The game originally scheduled for Saturday night will become part of a split doubleheader on Sunday. The first game is slated to start at 1:35 p.m., and the nightcap is scheduled for 7:35 p.m.
The games will be made up as a single-admission doubleheader Sept. 8.
However, later Friday, it was decided that the evening game would be postponed and made up Sept. 15 at an undetermined time.
"We felt it was necessary and prudent to move the Sunday game to Saturday," Red Sox president and CEO Larry Lucchino said Thursday. "This will not only give us the best opportunity to play the scheduled games, but also help to ensure that traveling conditions are safer for our fans."
Little League World Series
The championship game of the Little League World Series has been moved back three hours to noon Sunday with Hurricane Irene expected to hit Pennsylvania.
Little League officials say the consolation game, which had been scheduled for 11 a.m. Sunday, has been canceled and won't be played.
Officials say they will evaluate conditions leading up to the game and that they could postpone the game until Monday if conditions aren't suitable.
The winner of the two games on Saturday will face off in the championship. Japan faces Mexico in the international final and Huntington Beach, Calif., faces Billings, Mont., in the U.S. final.
The New Haven Open, the final WTA tuneup before the U.S. Open, which starts Monday, moved up its championship match to 1 p.m. ET Saturday, rather than the scheduled 5 p.m. ET.
"Right now it looks like the hurricane is not going to hit until early Sunday morning," said Anne Worcester, the tournament's director. "But, it's not just the actual playing time of the final, but our staff has to break down the site, so it has a lot to do with their safety."
At Flushing Meadows, the U.S. Tennis Association called off Arthur Ashe Kids' Day, a tennis-and-music event set for Saturday and scheduled to feature Novak Djokovic, defending champion Rafael Nadal and Carmelo Anthony of the New York Knicks.
Tennis officials said they would close the National Tennis Center on Sunday, with plans to reopen it Monday morning before play begins.
Major League Soccer's Philadelphia Union rescheduled Sunday's game against New England for 8 p.m. ET Sept. 7 at PPL Park in Pennsylvania, and the New York Red Bulls moved Sunday's game against the L.A. Galaxy to 8 p.m. ET Oct. 4 at Red Bull Arena.
D.C. United, scheduled to host the Portland Timbers at 2 p.m. ET Saturday, decided to postpone their game as well. No makeup game has been announced. The Timbers made arrangements to return to Portland Friday.
The PGA Tour on Friday reduced its first playoff event, The Barclays, to 54 holes because of the rain and potential damage expected. New Jersey already is under a hurricane warning, and officials feared up to 10 inches of rain could fall on Sunday.
The plan is to finish 36 holes Friday and start the third round first thing Saturday morning, with hopes of getting in a 54-hole event before the rain arrives.
If they can't finish Saturday, the tournament would become a 36-hole tournament, but left unclear was whether a 36-hole tournament would count as an official win.
Information from ESPNNewYork.com's Ohm Youngmisuk and Ian Begley and The Associated Press was used in this report.