The honeymoon is over for Robert Picard and the Washington Capitals. The man whose contract made him a potential lifetime Capital was traded to the Toronto Maple Leafs yesterday for goaltender Mike Palmateer.

The blockbuster deal, certainly the biggest in the Capital's six-year history, also sent winger Tim Coulis to Toronto. In addition, the Leafs took Washington's second-round pick in yesterday's NHL draft, while the Capitals received Toronto's third-round selection.

"We consider goaltending like a 7-foot-4 center in basketball, or the ace of a bullpen staff or a starting pitcher," said Washington General Manager Max McNab. "When the opportunity came, we felt we would kick ourselves if we passed it up. I hope it's another (Tony) Esposito story and we can forget about goaltending for another 10 years."

Palmateer, 26, became a free agent June 1 after four years with Toronto. Owner of a 3.02 career goals-against average, Palmateer quickly established himself as one of the NHL's best, although an ankle injury and dissatisfaction with the Leafs' management contributed to a subpar season in 1979-80.

Palmater, who had battled publicly with Leaf General Manager Punch Imlach almost daily last season, was approached by several teams, including at least one that offered more than the four-year, $800,000 contract he signed with Washington. But after enduring the endless hassles in Toronto, Palmateer was looking for happiness more than money. When he opted for Washington, the Capitals then worked out the deal rather than risk compensation.

"The next contract will be for a million," Palmateer said. "I considered the pluses and minuses of the different teams and I picked Washington because I think it will be a nice place to play, it's an up-and-coming team and there are a lot of positive things there. Playing for Gary Green, who's my own age, excites me.

"After all the negative things, I'm happy to be thinking positive. There was so much controversy here it was not funny. It's hard to explain how bad it was. I hurt my ankle (against Washington Dec. 26) and the injury lasted a month but I came back too soon and it cost me another month.

"I came back because everybody thought I was dogging it, when I was actually trying to get myself ready for the playoffs. I'd play with my whole body in a cast if it would help the team. I take pride in going out and giving my best every time.

"I don't want to sound too cocky, but I know I'm good and I guarantee that the Capitals will be in the play-offs next year. A goaltender is only as good as his team, but from all I've heard Washington is going to have a very good team."

Picard, 23, was Washington's No.1 pick in 1977 and his five-year contract contained a special clause that permitted the Capitals to match any offer from another club should Picard ever go the free-agent route.

Picard was the Capital's all-star representative the last two years and McNab had blunted previous trade rumors by saying that "Picard is a game-breaker who has not reached his potential and we can't afford to deal someone like that."

"It became a question of priorities," McNab said yesterday. "Palmateer is a game-breaker, too, in another way. One is a defensive game-breaker, the other an offensive game-breaker. We were prepared to live with Robert for the next 10 years."

Punch Imlach, Toronto's general manager, had sought Picard since Imlach was in Buffaalo and Picard was a junior star in Montreal. McNab resisted at that time, refusing to deal, Imlach the necessary draft pick, and had declined other overtures since. The Capitals' need for stable goaltending and Picard's inexplicable downturn last season broke his defenses. g

"I am not surprised, I'd be dumb if I was," Picard said. "I knew from the papers they were drafting an offensive-minded defenseman, they've wanted Palmateeer for awhile, Rick Green had signed. I know that two and two are four.

"I'm sort of disappointed, but I'm happy they did it now. I can sell my house and move. During the season it would be a lot tougher. But I've been confused since I came home this morning and they called me. It will probably take me two weeks to understand what has happened. I've never been traded before."

It has been a big month for Picard, who was married on May 24 and celebrated his 23rd birthday May 25. Now he heads into the maelstrom that has become hockey in Toronto, a pressure cooker equal to that anywhere in sports.

"This is a second wind for me," Picard said. "I'm entering a new life. I grew up in Montreal and there was pressure there, So I think I can handle the pressure in Toronto, too.

"It's a hockey town where everybody recognizes you. That was the big difference with Washington, where fewer people know about hockey. This could be good for me. I've always been mixed up with hockey people."

While Picard, the most valuable Capital of 1978-79, was answering the phone at his Upper Marlboro home to learn he had been traded, owner Abe Pollin, a few miles away at Capital Centre, was presenting a $2,000 ring to last season's MVP, Mike Gartner.