Washington's weekend of waiting, watching and wondering goes on for another agonizing afternoon.

Although the Redskins' playoff hopes still are flickering after their 27-16 victory over the St. Louis Cardinals yesterday at Busch Stadium, they will need help from a most unlikely source to extend their season. The Redskins will make the playoffs only if the Dallas Cowboys beat or tie the San Francisco 49ers today at 4 p.m. in Candlestick Park (WDVM-TV-9).

Cheer for the Cowboys? "I didn't think I'd ever do that, but I'm afraid I'll have to," Redskins Coach Joe Gibbs said yesterday.

Gibbs' team stayed alive the hard way, rallying from an early 9-0 deficit. By the middle of the third quarter, after George Rogers' one-yard touchdown run had given Washington a 20-9 lead, it was breathe-easier time. Rogers gained a team-record 206 yards rushing against the Cardinals, whose owner fired the entire coaching staff after the game.

The New York Giants earned one playoff spot earlier in the day by beating the Pittsburgh Steelers, 28-10, and are scheduled to play host to the NFC wild-card game next Sunday.

The Cowboys do have incentive today. A victory, combined with a Los Angeles Rams loss to the Raiders Monday night, would give Dallas the home-field advantage against the Rams in the playoffs. Then again, San Francisco must win to reach the playoffs.

It all will be determined today