Chris Evert struggled to a tense victory over Billie Jean King, still her toughest opponent psychologically, on Centre Court at Wimbledon yesterday. But the most dramatic episode of the women's quarterfinals occurred in the less majestic confines of Court No. 3, in a match between Evonne Goolagong and Virginia Ruzici.

Goolagong suffered an adverse reaction to cortisone injection she had taken for an inflamed Achilles' tendon., and it "seized up" during the first set. As she served at 2-5, having lost five games in a row and started limping noticeably, she turned ashen, burst into tears and appeared on the verge of defaulting.

Her husband, Roger Cawley, rushed onto the court. He knew it was against the rules of tennis for a stricken player to receive aid, but said later: "I was afraid she might keel over. She was wobbly and crying. It was just a human reaction. What would you do if your wife was crying?"

Evonne sat down on her chair, a few yards from the baffled umpire. Her husband comforted her as she sobbed into a towel.

Then the 26-year-old Australian, who has long been noted for her sunny disposition and sportmanship, composed herself, tested her left heel, and went back on court.

Goolagong won five games in a row to take the first set from a clearly shaken and suddenly erratic Ruzici. Goolagong lost the first three games of the second set, then cracked clusters of winners to seize the last six games and the match, 7-5, 6-3.

In today's semifinals, Goolagong will paly No. 2 seed Martina Navratilova, the 21-year-old expatriate Czech lefthander, who steamrolled South African Maris Kruger, 6-2, 6-4.

Evert raised her game a notch to capture the last four games of a 6-3, 3-6, 6-2 victory over King, and will meet defending champion Virginia Wade in a rematch of last year's most startling semifinal.

Wade, who ended 15 years of frustration here last summer by winning the game's most cherished title in Wimbledon's centennial year, was sharp and eager in clobbering Mima Jansovec, 6-0, 6-4.

The Exert King match seemed to be building to a memorable denouement until King lost her serve from 40-0 at 22 in the final set. The match provided the most intetesting tennis, even though an inflamed heel robbed King, 34, of her usual mobility.

But it was the bizarre Goolagong-Ruzici contest that offered pathos that will live on in Wimbledon lore.

Goolagong the champion of 1971 and three times runner-up, was limping throughout the first set. But it was not until she was serving at 2-5, [WORDS ILLEGIBLE] the the full extent of her distress became evident.

She stopped in the middle of the game and put her head in her hands. Tears streamed down her cheeks. She motioned to the umpire forlornly, and hobbled toward her chair, dazed and wobbly.

Her husband, sitting on a courtside bench was on court in a flash. After she pulled herself together, he asked her, "Are you sure you want to play on?" She said, "Yes."

When play resumed, Ruzici, 23 - a slender Romanian who won the German and French opens over weak [WORDS ILLEGIBLE] this summer - hit a forehand passing shot. But she was upset, obviously unsettled to be playing an opponent she feared might be badly instead.

Ruzici looked to her friend Mitch [WORD ILLEGIBLE] , confidant of many East European players. "What do I do?" she asked, her liquid eyes sad and troubled.

"Just play the match," he said.

Down 0-30 in the next game, she [WORD ILLEGIBLE] a ball into the canvas backstop at her end of the court. She netted a forehand to lose her serve and was never in the set again.

"When Evonne started crying. I got soft in the head. I hate to say this, but the reason I lost is that I lost my concentration when I shouldn't have," Ruzici said. "I was really upset by the whole thing."

She could have claimed the match by default under the rules, but never seriously considered doing so.

"I knew it was against the rules to go on the court, but I didn't think she could make it to the chair on her own." Cawley, a former British junior tournament player, said later.

"I knew it might cost her the match, but my instinctive reaction was to help her. I thought the match would be over at the point anyway. I couldn't just stand there.

"It's a shame that Ruzici fell apart after that. She got very tight, and Evonne just started swinging away and hitting winners. She could have claimed the match, but I think she knew that if the situation had been reversed, Evonne wouldn't have done that."

Neither Evert nor King played her best tennis - Evert felt she was overly tentative, and King's lateral movement and zest for long rallies was restricted by the inflamed heel for which she had another Novocain injection - but their match was much closer than any of their six meetings the last two years. In those, including meetings in the quarterfinals here a year ago and the U.S. Open in September, King won a total of only 19 games.

This time King, the six-time singles champion here whose aggressive game is much better suited to grass courts than is Evert's baseline style, kept the pressure on by swarming to the net behind her serve, approach shots and punishing returns of Evert's second serve.

The turning point came with King serving at 2-3, 40-0 in the final set. Evert smacked a forehand return winner, King netted an ill-advised drop shot from the baseline ("just dumb") and Evert walloped a forehand down-the-line pass on the dead run, off a scrambling point.

At deuce, King zapped what looked like a winning serve wide to the forehand. Evert just got her racket on it and lobbed the return. The ball fluttered in the wind and fell in King's forehand corner. She lobbed it back very short, and Evert crunched away an overhead.

On the break point, Evert buzzed backhand cross-court passing shot on the sideline - the same point she hit to break at love for the match two games later.