The last time Miami Dolphins quarterback Dan Marino threw a pass toward Mark Duper, late in the fourth period yesterday, Redskins cornerback Anthony Washington leaped and batted the ball away.

As Duper got up from the RFK Stadium grass, he slapped Washington across the leg.

"Nice coverage," said Duper.

"I was serious, but he didn't say anything back," added Duper. "He might have still been thinking about some of the things that had happened earlier."

Duper, a 5-foot-9 speedster from Northwestern (La.) State, had a lot of the Redskins thinking yesterday.

For starters, Duper beat Anthony Washington on two long passes and eluded the Redskins' coverage even when double teamed, making six receptions for 178 yards and two touchdowns.

Jim Jensen, one of Miami's top special teams players and its third-string quarterback, was a surprise starter at wide receiver and also caught two touchdown passes from Marino in the Dolphins' 35-17 victory.

Marino completed 21 of 28 passes for 311 yards and five touchdowns. He didn't throw any interceptions, nor was he sacked.

"When you have as much time to throw as I did, it isn't that hard to complete some passes," said Marino.

"We went into the game planning to throw," said Miami Coach Don Shula.

To make that easier, Shula departed from the norm and started Jensen and only one running back.

"We felt they (the Redskins) would double cover Duper and that would leave Jensen isolated on a strong safety. That's a matchup we wanted," said Shula.

Jensen got his opportunity partly because Jimmy Cefalo, who missed all of last season with a knee injury, is still not at full strength.

"I really don't know what to do with Jensen," said Shula, "so I let him do a bit of everything."

Jensen, who said he didn't know he was going to start until the first play of the game, "when I was told to go out there," added that he felt the Redskins' secondary "was mixed up a lot. They just didn't seem to know where to line up some times."

Said Marino, "Our game plan was to spread them out."

Marino went first to Duper on a 26-yard touchdown pass over Darrell Green in the first period.

"That play was what we call a takeoff," said Duper. "We send four guys deep and I had Green, man to man. I saw the ball coming and I don't think he did and I was able to come back and catch it."

Green was called for pass interference on the play, trying to find the ball.

The Dolphins were trailing, 10-7, when Marino and Duper combined for a 74-yard score. This time, Duper beat Anthony Washington and Green.

"Washington tried to jam me, but I got by him and looked for the ball right away," said Duper. "I knew they were in a double zone and he (Washington) wasn't going to chase me, and I caught the ball before the deep man could come over and help. Then, I just ran."

Green missed a diving tackle at about the 40 and there was no one left to catch Duper.

"It wasn't really a great throw," said Marino. "Duper was open and I just tried to get the ball to him. I can't take all of the credit for our performance today. I had a lot of help. Duper takes a 20-yard pass and goes 70 yards with it -- I'd say that was a lot of help, wouldn't you?"

"He (Duper) played a great game; he simply outran me. I think I should have had him man to man, but he beat me," Anthony Washington said.

The Dolphins scored three more times in the third period on Marino's pass to wide receiver Mark Clayton and two more to Jensen. Jensen's first score was set up by a 46-yard pass from Marino to Duper on which Duper, even though Anthony Washington was giving him a 10-yard cushion, breezed past him on a streak pattern.

By then, the Redskins were so conscious of Duper that the other Miami receivers were open.

"By that time, they were rotating their coverage toward Duper," said Marino.

Jensen beat Tony Peters on a six-yard touchdown pass; then Clayton beat Green on a nine-yarder; followed by Jensen beating Mark Murphy on an 11-yarder to put the game out of reach.

"On the second catch, I was so open, I had time to stand there and wave my arms," said Jensen. "Eventually, Murphy came over and picked me up, but it was too late."

"Everything we tossed at them we got burned on," Murphy said. "We blitzed and got burned; when we didn't blitz, we got burned. We tried several different coverages that we thought would work, but none of them did."

"Everything that could happen bad, did," Peters said. "They kept us off balance with those quick passes to the wide receivers and then they got us deep. Based on the last two games we played against them, we thought they'd go outside on us.

"We expected them to bomb us, but we thought they would send the wide receivers out and up. But they went the other way (straight up the middle)."

Shula was concerned about Marino before the game because a broken index finger on his throwing (right) hand had limited him to playing only the final preseason game. Marino played that game with a splint, but didn't wear any protective devices yesterday.

The finger was swollen and discolored after the game and Marino said he expects it will be that way all season. "There's some calcium in there," he said, "but I can still throw."