Fifteen years ago in deepest New Jersey, Drew Pearson graduated from South River High School after breaking all the quarterbacking records of his predecessor, Joe Theismann.

Pearson has long since proved himself one of the best receivers in the game, but for an instant today, he was back on the issuing end of a game-winning pass--a 49-yard flea-flicker to Tony Hill that put the Dallas Cowboys within three feet of finishing off the Green Bay Packers.

The pass came with less than five minutes remaining and Dallas leading, 30-26. On the next play, Robert Newhouse, playing for the injured Ron Springs, scored from the one and the day's scoring ended at 37-26.

The Cowboys will face the Redskins--and Pearson's old schoolmate--for the NFC championship Saturday at RFK Stadium. The winner will play in Super Bowl XVII in Pasadena, Calif., Jan. 30. On Dec. 5, the Cowboys beat the Redskins, 24-10, at RFK for Washington's only loss of the season.

After today's game, Pearson proved as proud and defensive as any quarterback: "The pass wouldn't have wobbled if I hadn't had my gloves on. But I didn't want to take them off and give away the play . . . Tony Hill made me look bad with all his whirling around before making the catch."

"That's Drew Pearson for you," said Hill. "There's about 20 guys on our team who think they're quarterbacks and want to throw that play. I've been trying to get them to let me do it for a long time."

Coming into this season, Pearson had completed four passes in four attempts for three touchdowns. This year the 10-year receiver is two for three. As if the upcoming championship contest required even more incentive for Pearson, the Redskins' Vernon Dean intercepted one of his passes in the teams' last game.

Although the Cowboys were able to hold onto the ball for 38:52--nearly two-thirds of the game--the Packers proved anything but compliant.

"They made big plays," said Tony Dorsett, who finished with 99 yards in 27 carries. "It's scary. It's two weeks in a row that we've been ahead in the stats and almost lost."

With Dallas leading at the end of the third quarter, 23-13, Green Bay opened the final period with a big play, indeed. Wide receiver James Lofton took a handoff from running back Eddie Lee Ivery and ran 71 yards for a touchdown behind a crushing lead block from his quarterback, Lynn Dickey. Rod Hill blocked Jan Stenerud's extra-point attempt and the score was 23-19.

Lofton's end-around took on the shape of a question mark as he made his way downfield, and the Cowboys were quick to answer it.

Starting from his 20, Danny White led a crack drive with passes to Hill and Timmy Newsome. After two runs by Dorsett for seven and two yards, White passed to Doug Cosbie on third down for a seven-yard touchdown pass and a 30-19 lead with 9:50 remaining.

Green Bay's next drive stalled, but this time the defense came up with a big play. White, looking for Newsome, was intercepted by cornerback Mark Lee, who returned the ball 22 yards for a touchdown with 4:24 remaining. Again the margin was four points, 30-26.

The Cowboys got the ball back, and after making their way to midfield, they turned to erstwhile quarterback Pearson, who showed off the glory of his high school years to the crowd of 63,972 at Texas Stadium. There were 1,104 no-shows.

In the Dallas end zone with 0:16 left, Dennis Thurman intercepted his third pass of the game to finish off Green Bay's final drive of the season.

Dallas' Rafael Septien kicked field goals of 50, 34 and 24 yards for 14 straight playoff field goals. White, the Cowboys' other passer, threw 36 times for 23 completions, 225 yards, one interception and one touchdown.

Bart Starr, who led the Packers to victory in the fabled "Ice Bowl" of 1967 with his game-winning quarterback sneak in the closing seconds, did not appear disconsolate after his first playoff game as coach.

"It's disappointing to lose certainly, but we hope there will be a carry-over of the good things we've done this year into the next," said Starr. "We feel there has been a lot learned from the experience of the playoffs."

The Packers ran only eight plays from scrimmage in the first quarter, but they were able to stay in the game on the strength of their defense. They even had a 7-6 lead with 10:06 left in the first half after Dickey threw to Lofton for a six-yard scoring pass.

But an 80-yard, 13-play drive ended by Newsome's two-yard run with 1:18 left in the half, and a 39-yard interception for a touchdown by Thurman 14 seconds later, made things all the more difficult for the Packers. The half ended with Green Bay trailing, 20-7.

Two field goals by Stenerud and one by Septien in the third quarter set the stage for the fourth-period excitement.

Minutes after the game, Dallas Coach Tom Landry looked ahead to the NFC championship game: "Now we have to go to Washington and play before their crowd. Up there, you just hope you can hear the signal count."

White sounded an uncharacteristically acrimonious note: "That's going to be the greatest game of the year. They don't like us and we don't like them. I hope they have 90-foot fences around the field."

"We've been beaten the last two years in the championship game," said Dorsett. "Yesterday I was sitting in my living room and heard the chant in Washington that they want Dallas. We're going up there like good doctors. We have a house call to make."