Defending champion Simona Halep crashed out of the 2019 French Open on Thursday as she was well beaten by 17-year-old American Amanda Anisimova in the quarter-finals.

The teenager needed just 68 minutes to beat Halep 6-2, 6-4 and end her chances of back-to-back triumphs at Roland Garros.

Anisimova will now face Ashleigh Barty in the last four after the eighth seed beat Madison Keys 6-3, 7-5 on Thursday.

Women's Singles Results

Amanda Anisimova bt. (3) Simona Halep: 6-2, 6-4 

(8) Ashleigh Barty bt. (14) Madison Keys: 6-3, 7-5

Men's Singles Results

(1) Novak Djokovic bt. (8) Alexander Zverev: 7-5, 6-2, 6-2 

(4) Dominic Thiem bt. Karen Khachanov: 6-2, 6-4, 6-2

For a look at all Thursday's results, visit RolandGarros.com.

Thursday Recap

When Johanna Konta knocked Sloane Stephens out of the tournament on Tuesday, the draw looked to be opening up for Halep.

As the third seed, she was the highest-ranked player left in the tournament and by far the most experienced given her three previous appearances in Roland Garros finals.

However, the unseeded Anisimova had the Romanian under pressure from the off, dragging her back and forth along the baseline with some brilliant hitting.

Anisimova took the first break of the match for 4-2, saved a break point as she moved to 5-2, and then broke again to take a shock one-set lead against Halep.

In only her second Roland Garros appearance, Anisimova was dominating one of the world's best clay-court players in the last eight, and she continued in the second set as she took a 3-0 lead:

After saving three break points to go 4-1 ahead, the American finally stuttered as Halep broke back.

But at 5-4 ahead, she was given a match-point opportunity when Halep double-faulted, and Anisimova duly took it with a trademark thumping backhand:

After Thursday's performance, Barty will be aware Anisimova will be no pushover in the semis.

But the Australian takes her own good form into the last four after a fine display against Keys.

Keys, the No. 14 seed, was a dangerous opponent for Barty given she made the last four at Roland Garros last year.

The world No. 8 had never previously made it as far as the semi-finals at a Grand Slam nor had she got past the second round at the French Open.

She is now a semi-finalist in Paris following a straight-sets victory against Keys, who was not exactly subpar:

Barty's impeccable variation was notable against the American, as she won 11 out of 12 points at the net.

She also dealt well with Keys' big serve and won 80 percent of points behind her own first serve.

The 23-year-old had only one moment of concern when she suffered her only break in the whole match and served for victory at 5-4 ahead in the second.

But, after Keys handed the break back in the next game, Barty made no mistake to serve out at the second time of asking and take victory in 69 minutes. 

The men's side saw a pair of easy straight-sets victories. Novak Djokovic and Dominic Thiem each cruised through their quarterfinals matches to set up a semis clash Friday.

Djokovic took down Alexander Zverev 7-5, 6-2, 6-2 in easy fashion, while Thiem breezed past Karen Khachanov 6-2, 6-4, 6-2.