Chris Evert Lloyd, who was contemplating retirement from tennis five months ago because her competitive fires had dwindled to glowing embers, today dethroned 1978-79 champion Martina Navratilova, 4-6, 6-4, 6-2, with a resolute, if unspectacular, performance, reaching the singles final at Wimbledon for the fifth time in nine years.

Evert, 25, who won the game's oldest and most revered title in 1974 and 1976 and was runner-up to Navratilova the last two years, seemed out of the match when she trailed, 4-6, 1-3, and had three break points against her for 1-4.

But feeling no pressure in her unaccustomed role as underdog and crowd favorite on the Centre Court, she kept fighting with a resilient spirit that delighted her many admirers. Playing smartly and adventurously, Evert was there to pick up the pieces when Navratilova's aggressive game fell apart.

Evert, who now has won 50 Wimbledon singles matches and 25 matches without a defeat since returning to competition in early May, will play an old rival, 1971 champion Evonne Goolagong Cawley, for the women's title Friday afternoon.

Bjorn Borg, seeking to become the first man since Lawrie Doherty in 1902-06 to win the men's singles title five years running, reached the final by crushing Brian Gottfried, 6-2, 4-6, 6-2, 6-0.

As if he needed an edge, Borg will have a day off Friday as John McEnroe plays fellow left-hander Jimmy Connors in the other semifinal, being played a day late because of the rain that snarled scheduling earlier in the tournament.

Connors, the champion of 1974 and runner-up to Borg in 1977-78, today beat last year's runner-up, Roscoe Tanner, 1-6, 6-2, 4-6, 6-2, 6-2, in a quarterfinal match that was much more tedious than the scores imply. The tennis was mediocre at best, dreadful at worst. Tanner had a poor day serving and Connors an off-day returning serve.

Only in the first set did this match crackle with any electricity. Tanner served five of his 15 aces and a number of good, kicking second serves. Connors won only 12 points in the set, but even then Tanner's low first-serve accuracy (12 for 25) forshadowed trouble for him.

By the end of the hit-or-miss match, Tanner's percentage had plummeted to a dismal 44 percent (62 of 140 first serves in court), and his second serves had gotten shorter and more timid. He was not consistent enough with either his ground strokes or his volley to compensate for this deficiency, and eventually Connors hit enough punishing returns to knock him out.

"He only had to return the second serve. Actually, I don't think he played that well and I don't think it was all that great a match," Tanner said with a candor unknown to Connors, who always says that he played well when he wins and tries to make even a boring clunker like this one sound like a classic.

"If he had been returning well, he would have beaten me in four sets," Tanner continued. "I just served badly. I tried to take something off the first serve after awhile and just get it in, but that didn't work. The problem with doing that against somebody of Jimmy's ability is that sooner or later, he's going to get to it. And he did."

It took a long time. For much of the 2-hour 37-minute match Connors was slugging balls into the net, cursing, making rude gestures to himself and the crowd, and grabbing his groin in a characteristic gesture of frustration that only he seems to find amusing. At one point, he dropped his racket and raised the middle finger of both hands at once, giving new meaning to the term "double-digit inflation."

When Tanner is serving well, or hitting his hard, penetrating ground strokes in the court with some regularity, he is a threat to beat anyone on a grass court. But today he did neither, and so he knew he was doomed. "On second serves," he said, "I was going to the net swallowing as I came in."

Tanner did manage to win the third set with a single service break in the ninth game, smoking a backhand cross-court return winner after Connors netted one of his grunting, "skyhook" overheads. Connors has saved four break points two games earlier, when he also scared himself briefly by twisting an ankle running for a wide forehand.

But in the last two sets, Tanner looked much more like the erratic slasher of old than the more complete player who took Borg to five scintillating sets in the last year's final.

Connors had seven chances to hammer the final nail into his coffin in the fifth set -- two break points at 2-1, five more at 3-2. The first six times, he didn't get his service return over the net, but on the last he cracked a backhand return winner off a short second serve, and lost only three more points thereafter.

Connors now plays McEnroe, whom he has beaten in four of their last five meetings, for the dubious honor of playing Borg in the final. Tanner is picking McEnroe to win the semifinal. "Mac is much better than I played today, and I was in the fifth set," he said.

Borg had no trouble today except for a one-game lapse that cost him the second set. Serving at 4-5, he double-faulted twice to 15-30, hit a little forehand into the net off a bad bounce, then muffed a forehand angled volley off a hard topspin backhanded by Gottfried.

The pivotal point in the match came with Gottfried serving at 1-1 in the third set, after Borg had ripped a forehand pass for 30-30. Gottfried got to midcourt and pounded three deep smashes, but each time Borg retreived them -- twice with high-arc backhand lobs and then with a hard forehand that forced Gottfried to net a backhand volley.

Discouraged, winded and facing break point, Gottfried netted a forehand volley off one of Borg's typically fizzing topspin returns. He won only one more game thereafter.

As he has throughout the tournament -- in beating Ismail Elshafei, Shlomo Glickstein, Rod Frawley, Balazs-Taroczy, Gene Mayer and Gottfried in what must be considered one of the all-time big draws -- Borg followed his first serve to the net and west in repeatedly behind both sliced and thumping topspin approaches.

Borg thinks it is necessary to play the net because the ball is staying very low on the grass, making it difficult for him to play his usual back-court style. But his coach, Lennart Bergelin, is concerned that Borg is relying too much on his volley.

"Now he has in his head maybe that he has to go in all the time. I want him to stay back sometimes, to hit his topspin off both sides instead of the backhand slice, so that he will have confidence in both," Bergelin said. "That way he can change the game when he needs to."

Evert changed her normal tactics, coming off the baseline to challenge Navratilova's vulnerable left-handed backhand, in the day's most dramatic match.

"I felt that's what won the match for me, when I started to put pressure on her coming to the net," said Evert, who used to treat the forecourt like a minefield, but has worked on her net game with husband, John, a British Davis Cup player.

"If I stand in the backcourt against Martina on grass, she just takes her time and picks her shots to come in to the net, and then I'm in trouble," said Evert, who reached the semifinals of her first Wimbledon in 1972, and has done at least as well every year since.

"I didn't even have to hit many volleys, because she was missing her passing shots."

The standard of play was spotty, at best. In the first set, Evert was tentative on the forehand, and uncertain as to her plan of attack. Navratilova, whose explosive game is better suited to grass, never served well, and her normally reliable volley disintegrated in the second and third sets.

Navratilova won the first set comfortably, and had two break points in the first game of the second, Evert saving the second with a lunging backhand volley that wobbled over the net and practically bounced back into it. b

Evert lost her serve in the third game, hitting another shaky forehand wide, and had three break points against her at 1-3. On the first, Navratilova netted a forehand, and then Evert -- digging in like the player who ranked No. 1 in the world for five years before Navratilova supplanted her last year -- buzzed two passing shots.

Eventually, it was Navratilova who cracked. Serving at 5-4 in the second set, she double-faulted twice to 30-40. She saved one set point, but Evert got a second with a backhand pass. Then came the most controversial point of the match.

Evert's backhand return of a short second serve looked several inches long, but the linesman called it good.

Navratilova looked at him, screamed, then kept playing the point nervously, eventually sailing a forehand.

She hurled down her racket, and appealed to the umpire, but he refused to overrule the call. Game and set to Evert.

How much did that call affect Navratilova?

"Maybe a lot, maybe nothing," she said. "I got upset, but I think that just fired me up even more, because I won the next game." She broke Evert for 1-0 and 2-1 leads in the final set, but then played horrendously to let Evert back in.

"I lost my serve because I volleyed terribly, and then I broke again and volleyed even worse," said Navratilova, who bungled three volleys from 2-1, 30-15. "So I don't think that call had anything to do with me losing, although if I had been at deuce, then a lot of things could have happened . . . The sad thing about it was that there was no way I could come back. It was at set point, so the set is over."

Evert lobbed well on a breezy day, making Navratilova pay for crowding the net, and she deserved good marks for the variety of her tactics after the first set. But the most admirable quality of her victory today was her will to stay in the match and turn it around -- the very things whose temporary departure made her take three months off early this year and ponder her future in the game.

Having lost four times in a row to Navratilova, beginning with last year's Wimbledon final, and four times in a row to Tracy Austin (Goolagong's semifinal victim), starting in the U.S. Open final, Evert had begun to think the gumption that made her great was gone forever. Today, she has it. And the crowd of 15,000 at Centre Court loved her for it.