Maria Sharapova Into Wimbledon Semifinals

Maria Sharapova survived a gamesmanship row to set up a potential Wimbledon showdown with old rival Serena Williams as the Russian battled into the semi-finals with a 6-3, 6-7 (3/7), 6-2 victory over Coco Vandeweghe on Tuesday.

Sharapova needed two hours and 45 minutes before she finally saw off unseeded Vandeweghe to reach her fifth Wimbledon semi-final and her first since 2011.

But the world number four was accused of unsporting behaviour by Vandeweghe, who was unhappy that Sharapova was moving during the 23-year-old American's service action.

Vandeweghe protested to the umpire during the quarter-final and repeated her complaint in the post-match press conference

"She (the umpire) said she didn't believe she was doing it during the motion. I strongly disagreed. Towards the later end of the second set, I said if she has a problem speaking to Maria, if she's too scared to do it, I had no problem speaking to her," said the American.

Joining Sharapova in the last four was 20th seed Garbine Muguruza, who defeated Swiss 15th seed Timea Bacsinszky 7-5, 6-3 to become the first Spanish woman to make the Wimbledon semi-finals since Arantxa Sanchez-Vicario in 1997.

Sharapova was well below her best on Centre Court, making 23 unforced errors, serving 10 double faults and hitting only 19 winners.

But the always tenacious 28-year-old somehow found a way to secure her 20th Grand Slam semi-final appearance that has brought her five major titles.

"It's been a while since I've been at the semi-final stage here so I'm really happy. It gives me a lot of confidence," Sharapova said.

"She was playing with nothing to lose, so I knew it was going to be tough.

"But you have to give everything you have on a special occasion on a special court. I regrouped in the third and got it done."

- Familiar figure -

Lying in wait for Sharapova in Thursday's semi-finals is likely to be the familiar figure of five-time Wimbledon champion Serena, who was due to face former world number one Victoria Azarenka later on Tuesday.

The 33-year-old American, who famously lost to the teenage Sharapova in the 2004 Wimbledon final, has now won 17 of their 19 meetings.

Before she can think about extending that dominant run against Sharapova, Williams -- chasing a 21st major title and potential calendar Grand Slam -- must see off Azarenka.

Azarenka is seeded 23rd after an injury-plagued period, but the Belarusian has twice come close to defeating Serena in the last two months, failing to convert on three match points and losing in the round of 16 in Madrid and then losing a 6-3, 4-2 lead in the third round of the French Open.

Overall, Serena leads Azarenka 16-3 and has never lost to her in a Grand Slam event, despite Azarenka's pushing her to three sets in the 2012 and 2013 US Open finals.

The quarter-finalists in the bottom half of this year's draw are made up of four women who have never won a Grand Slam title or reached the number one ranking.

It was Muguruza who took the giant leap towards the sport's upper echelons as she defeated Bacsinszky, a surprise French Open semi-finalist last month, in 86 minutes on Court One.

To reach the quarter-finals, Muguruza beat fifth seed and former world number one Caroline Wozniacki on Monday and also defeated 10th seed Angelique Kerber in the third round.

The 21-year-old, born in Venezuela but raised as a tennis prodigy in Barcelona, had never been made the semi-finals of a Grand Slam.

She had fallen in the last eight of the French Open for the last years.

"It is just amazing. I am so happy. It was a very tough match and I am just so excited. It was a very intense final game so it is just relief," Muguruza said.

"It is very hard to make the last four of Wimbledon so to achieve this so I am very proud. "

Muguruza will take on Polish 13th seed Agnieszka Radwanska, the 2012 runner-up, or 21st seed Madison Keys of the United States for a place in the final.