LONDON, Great Britain - For the first time in five years, Simona Halep will play in the semifinals of Wimbledon.

The No.7 seed came through a tight opening set and eased through to the finish against unseeded Zhang Shuai, 7-6(4), 6-1, to become the first woman through to this year's final four.

The pair hadn't faced off in nearly three years, dating back to a 2016 season where Zhang not only stunned Halep in the first round of the Australian Open but also beat her on home soil in Beijing.

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"I expected her to play so well. She beat me the last two times that we played. I was a little bit nervous before the match, a little bit stressed. I knew that she's going to come and hit the balls very strong," Halep said after the match.

"When she hits...the ball doesn't bounce that much. It's really tough to return. But I kept fighting. I knew that I have to be 100% for every ball, then I will break her rhythm a little bit. It happened in the second set."

It was the World No.50 who came out of the gates hot, as she totaled five winners across the first two games as she was quick to settle in.

"I'm really happy I can make the quarterfinals and play on Court 1 against the, yeah, former No. 1," Zhang said in defeat.

"Today I had a really good start. I make, like, 4-1, 40-15 I think. Yeah, I try my best, play -- try to play more winners. After the 4-1, I made more mistakes, I think.

"She find really good rhythm after the few games. I...did nothing wrong, I just tried my best. Anyway, [I'm] really happy this year [with] Wimbledon."

Halep trailed 4-1 in the opening set, but came through what proved to be a crucial sixth game - where she saved four break points which would've seen her trail 5-1 - to win three straight games to level.

"Winning that...I really believed that I'm still in the set. If the score would have been, like, 5-1, I think the set would have been gone," Halep said.

"I just kept motivating myself and believed that I can turn it around."

Halep later won the first set in a tiebreak, winning five of the last seven points to claim her first set from Zhang in seven years, and eased through the second set behind a pair of late service breaks.

She continued: "I really think that she always played well against me, at least when she beat me it was really tough to return the balls and to get the rhythm.

"I knew that I had to be strong and not going back too far from the court, so I stayed a little bit more aggressive. She serves very, very well. She hits the ball strong.

"I think she improved in forehand also. It's strong on both ways. I think she has a great game."