Mice Marson's endangered hockey career was given a four-year injection yesterday. Marson received a three-year contract, plus an option, from the Washington Capitals at a modest salary. In exchange, he agreed to fore-go the six-figure amount contained in the option year remaining on his contract.

Marson, only 18 at the time, was drafted in the second round of the June 1974, amateur draft, as an under-age selection, and suddenly found himself with an excess of money and a lack of maturity to administer its consequences.

A summer of the good life brought a 222-pound Marson to the Capitals' training camp in London, Ontario. On a 5-foot-9 frame, that was about 25 pounds too much. But an even bigger burden was the fact tht Marson was the only black player in the National Hockey League.

When the team arrived at Capital Centre for an early exhibition game, several television commercial were filmed to introduce the more prominent players to the community. Marson was among the handful selected and shunned veteran Dave Kryskow shouted, in words audible throughout the empty building, "If I get my face painted, will you pick me?"

It was the beginning of player resentment that could not be quenched, no matter how hard Marson tried. Everywhere the team went, he was the player most sought out by the media.

In Boston, the Capitals were routed, 10-4, and Marosn's contribution consisted of standing around in awe while the Bruins scored three first-period goals. Quickly benched, he had nothing further to do until swarms of writers descended on the Capitals' dressing room after the game. Then he was the center of attraction.

During a game in Vancouver, Marson was knocked unconsciously and left the game for a while. A reporter entering the dressing room sought out Marson first, to see if he was all right. Afterward, in a restaurant, goalie Michel Belhumeur approached the reporter, and asked, "Why'd you run right to Marson? Was he the star of the game?"

Capital Centre fans did not heckle Marson while they had Greg Joly to chastise. But after Joly tore ligaments in his right knee in December of that year, attention turned to Marson as the guy who wasn't earning his salary. It was not a pleasant experience for a 19-year-old rookie.

Still, there were bright spots. Marson, a physical sort, flatterned Philadelphia's belligerent Don Saleski. In an exhibition against Detroit, he scored three goals on hard, accurate shots. In a 3-3 tie with Boston, he scored twice and was voted No. 1 star, over Bobby Orr and Phil Esposito. With 16 goals, he ranked third on the team.

The following year Marson warmed the bench, then drifted to the American Hockey League, where he spent most of his last season. Scoreless in a 10-game midseason visit with th Capitals, his career seemed headed for termination. Indeed, he admitted yesterday that he had thought carefully about collecting that option money and going off to college.

"I think I would heve kicked myself in the behind years later," Marson said. "Why come this far and quit? I want to be a solid hockey player in the National Hockey League for the Washington Capitals. I've been skating since I was 3 and playing hockey since I was 10. I'm a hockey player."

Marson will report to the Capitals' training camp at Hershey, Pa., Sept. 19 as a young player with promise. He and the Capitals' general manager, Max McNab, hope his modest salary will elminate both pressure and teammates' resentment.

"I think I've relieved myself of a lot of the business I went through," Marson said. "There's no question all that attention to me helped to split the team, plus the resentment over my salary. I think one reason the team has done better is what everybody is thinking collectvely, looking out for each other.

"I'm happier today than when I signed that big contract three years ago. I was a difficult situation playing in Springfield making money I was making. Now what I get out of the game the game I will have worked for and deserved."

McNab wasn't around to see those flashes of promise in the teen-aged Marson, but he watched the young left wing in Springfield last season and said, "The most encouraging part of Mike's career was his play in the last two months.

"When we're scouting, there are certain requirements we demand. They are the ability to initiate aggressiveness, physical size and strength, and better-than-average skating ability. Mike has all of them. His basic skills have to be refined, but we have the time. He's just turned 22 and his attitude is excellent.

"The underage draft was a horrendous mistake and it was worse for an player drafted by an expansion hockey club. The New York Islanders were able to send Bryan Trottier back for another year of junior, but the Capitals were in a different situation. There was pressure on the player's part to repay the big contract with results. There was an awful lot of pressure on Mike."

The new arrangement, one unique in sports, eliminate part of the pressure, but Mason still can't escape the fact that he is a black player in a white man's game. The presence on the Capitals of Bill Riley divides the onslaught a bit, but, it is worth noting this reporter during the Stanley Cup playoffs was, "Is Mike Marson going to make it?"

"I have to concentrate on hockey," Marson said. "The fact that I'm black is not going to pressure. It's not what you are but who you are. Be proud of who you are."