MIAMI, DEC. 20 -- Mark Duper hasn't had the season the Miami Dolphins expected from one of the league's top receivers, but he was eager to meet the pass defense of the Washington Redskins head on.

Duper, who had only 26 catches before tonight, caught six for 170 yards and three touchdowns, including the game-winner with 1:07 remaining, as the Dolphins remained alive for an AFC playoff berth with a 23-21 victory.

"Not many teams play a wide receiver with just a cornerback like Washington does," said Duper. "Mark Clayton and I are used to double coverage most of the time, so we were looking forward to this. Our game plan was to get the ball to our outside receivers, and that is what we practiced all week."

The practice payed off on Miami's final drive when quarterback Dan Marino took the Dolphins 80 yards in 13 plays after Miami took possession with 6:17 left trailing, 21-16.

On the drive, Marino threw completions of 16 yards to wide receiver James Pruitt, 23 to Clayton, 11 to Jim Jensen and the final six-yarder to Duper.

The winning catch, against Washington cornerback Dennis Woodberry, was a remarkable demonstration of Duper's concentration.

"I was lucky on the play," said Duper, who has had more yards receiving in four other games. "I think {Woodberry} stumbled onto the play. The ball hit me in the chest and I was waiting for it to come down, but I had to make sure I had my feet in the end zone. I was waiting and the ball just came back to my hands."

Miami Coach Don Shula said a few breaks like that, and Duper's overall performance, were owed the Dolphins in what had been an otherwise troubling season until three weeks ago.

"We were due to win a thriller," he said, noting the Dolphins have lost several games in the closing minutes. "There were some things that went on out there that were quite questionable, but I said three weeks ago that we just had to win the rest of our games, and so far, we've won three straight.

"Duper was just ready to explode. He had missed a game {with bruised ribs} and caught only a couple of balls in the games after he came back. You knew he was a great receiver and he had to have one of these nights."

The Redskins used some unfamiliar defensive alignments, such as a 3-4 front and switching of individual assignments. Shula said the switches caused some problems, but Marino, who threw for 393 yards, was sharp in the clutch.

"They were putting a lot of pressure on us with the blitz and Dan had to get some balls away quickly," said Shula. "But on the big plays, he was on the money."

Despite injuries that forced Miami to use inexperienced center Jeff Dellenbach and rookie tackle Mark Dennis, Marino was not sacked. That ended Washington's NFL-best streak of 63 straight games with at least one sack.

Marino's 26th career game with 300 or more yards passing moved him ahead of Sonny Jurgensen and into a tie for second place on the all-time list with Johnny Unitas (Dan Fouts has done it 51 times). He was confident he had a few more yards left in his arm during the final drive.

"We had nothing to lose and now we are starting to make the plays we didn't make earlier this year," said Marino. "We knew we had a chance to hit them on that play to Duper, and we had time left and we had four downs. We work on that pattern all year and it seemed like the time to use it."

Miami's largest crowd of the season -- 65,715 -- was grateful for Marino's confidence, but the person in the park most grateful was someone who never saw the play.

Miami safety Bud Brown was ejected with 8:32 remaining after he was called for spearing Washington quarterback Jay Schroeder on a late hit. Brown, who was called for a late out-of-bounds hit on tight end Clint Didier earlier, was thrown out when apparently he pushed head linesman Jerry Bergman. He was given two 15-yard penalties which led to the Redskins go-ahead touchdown with 6:17 left.

"I was under the stands and couldn't tell what was happening," Brown said of Duper's final touchdown. "But I could tell by the crowd noise what had happened. I was just praying that we would come back. I would have hated to blow the season on my stupid play."