Graf Struggles, Fernandez Sails Into Final : Australian Open: Sukova loses to two-time defending champion, 6-3, 3-6, 6-4. Porwik is no match for 18-year-old American, 6-2, 6-1.

Steffi Graf, suddenly looking vulnerable, had to come back from one service break down in the third set to defeat Helena Sukova, 6-3, 3-6, 6-4, Thursday in the women’s semifinals of the Australian Open.

“I’m far away from playing good tennis,” said Graf, who double-faulted four times in the first set and made 48 errors in the match.

“I just don’t have the right timing and the right feeling for it,” she said. “It’s good to know I won that match even though I didn’t play well.”

In the final, Graf will play 18-year-old Mary Joe Fernandez, who defeated Claudia Porwik of West Germany, 6-2, 6-1. Porwik had a break early in the tournament when she advanced because of an injury to Gabriela Sabatini, who had to default with a one-set lead against the West German.

Graf had not lost a set in 20 previous matches in the Australian Open and had defeated Sukova 14 times in a row. Sukova has defeated Graf only once, seven years ago when Graf was 13.

But Sukova has pulled major upsets before. She once broke Martina Navratilova’s record 74-match winning streak in the Australian Open in 1984. Graf came into this match with a personal-best winning streak of 46.

And Sukova had a service break and a 2-1 lead in the final set before Graf broke back and kept the set on serve through 5-4.

Sukova, serving to tie the set at 5-5, then gained a 40-30 lead. But she hit a backhand approach into the net, double-faulted and slapped a forehand wide to lose the game and the match.

“That’s the difference . . . when one of the players chokes,” said Sukova, who made 23 of her 50 errors in the third set. “I was winning the match and I gave it back to her.”

Graf said Sukova “could have definitely won that game. Still, that was the first game I said to myself, ‘You can still win the game.’ She made mistakes, which she didn’t do too often.”

Sukova, 24, whose late mother, Vera, was a finalist at Wimbledon in 1962, was a finalist at the Australian Open in 1984 and last year. She was also a finalist at the 1986 U.S. Open, but has never won a Grand Slam title.

Neither has the sixth-seeded Fernandez, but she was looking confident against Porwik, covering the baseline like a young Chris Evert and ripping passing shots by the West German.

The Floridian won the match in 67 minutes. She said she knew Porwik, 21, was nervous and took advantage of it.

“You could tell after the first couple of games, she was shaking her racket and hitting the ball up,” Fernandez said. “I tried to keep on top of her the whole match.”

Porwik said there was more to it.

“I was a little bit nervous playing in a semifinal for the first time in my life,” she conceded. “But really I think I was just too tired. I was physically tired and mentally tired and made too many mistakes.”

Porwik made 49 errors, 20 more than Fernandez.

Graf said Fernandez will present different problems than Sukova, but will still be a challenge.

“I take everybody seriously,” Graf said. “She’s been playing well. She’s had some tough matches and come through. Never in a Grand Slam final will you have an easy time.”

Porwik thought Fernandez would have only a slight chance against Graf.

“Steffi has to wait for her chances in the match,” Porwik said. “If Steffi waits for the right points to kill, she will have it easy in two sets. If she doesn’t wait, she can make a few mistakes because Mary Joe is very (solid).”

Fernandez concedes the task won’t be easy.

“She’s been there so many times,” she said of Graf. “I’ll have to take it to her. You have to forget about it and pretend you’re playing somebody else.

“I’m not one to get hyper. Concentration has been one of the best parts of my game since I was a little kid.”

In the men’s semifinals, defending champion Ivan Lendl will play Yannick Noah of France, who beat him in a tournament two weeks ago at Sydney.

Noah advanced by defeating Mikael Pernfors, 6-3, 7-5, 6-2. It earned the Frenchman his first appearance in a Grand Slam semifinal since he won the 1983 French Open. Pernfors, the Swedish-born former NCAA champion made the quarterfinals when John McEnroe was defaulted for a tantrum.