Cori “Coco” Gauff’s incredible run at Wimbledon came to an end Monday at the All England Club with a round of 16 loss to Simona Halep, the former No. 1 who took the match in straight sets, 6-3, 6-3.

Gauff, 15, exits the tournament along No. 1 Ashleigh Barty, who lost to American Alison Riske, on a “Manic Monday” that lived up to its name.

15-year-old Gauff out in fourth round

No. 7 Halep used her experience to advance past Gauff and make it to the tournament’s quarterfinals for a third time in four years. Gauff struggled with her forehand and had 29 unforced errors, though she battled throughout.

They exchanged points to start the first set, 2-2, before Romania’s Halep pulled away. Gauff went to the doctor during the second set and was given a tablet, prompting questions over if she was feeling sick, The Guardian reported.

Gauff’s parents thought they’d be back home for Fourth of July celebrations, but instead the 15-year-old American sensation ranked 313th in the world tore her way through the early Wimbledon schedule. The youngest person to ever reach Wimbledon’s main draw knocked out Venus Williams, 6-4, 6-4, in the opening round and gushed about sharing the court with the superstar.

Gauff advanced to the third round with a 6-3, 6-3 win over Magdalena Rybarikova fueled in part by the teenager’s powerful serve. It was then she showed how much fight she has with a rollercoaster victory over Polona Hercog 3-6, 7-6, 7-5, in her first appearance at Center Court.

Halep will play Shuai Zhang of China in the quarterfinal.

American upsets No. 1 Ashleigh Barty

Alison Riske, a 29-year-old Pittsburgh native, came back from a loss in the first set to knock out No. 1 Ashleigh Barty, 3-6, 6-2, 6-3, on Monday.

Barty is coming off a title at the French Open last month, her first Grand Slam singles title. Riske advanced to the quarterfinals of a Grand Slam for the first time in her career and defeated a top 5 ranked opponent for only the third time.

Riske, ranked 55th, has already won two grass court titles this season during back-to-back weeks last month. She’ll face Serena Williams in the quarterfinal.

Williams cruises to quarterfinals

Williams reached her 14th Wimbledon quarterfinal with a 6-2, 6-2 win over Carla Suarez Navarro. It’s her 51st Grand Slam quarterfinal for the seven-time Wimbledon champion.

Her last title at Wimbledon was in 2016 when she defeated Angelique Kerber, who knocked her out in the final last year in straight sets. Kerber lost in the second round and is out of this year’s tournament.

Rafael Nadal remains en route to 3rd title

The two-time Wimbledon champion advanced to his eighth straight Grand Slam quarterfinal with a 6-2, 6-2, 6-2 victory against Joao Sousa.

Nadal controlled rallies and limited mistakes, with only 10 unforced errors. The No. 2 ranked Nadal did not face a break point and won 78 percent of service points.

Nadal will face Sam Querrey of the U.S. in the quarterfinals. Querry is ranked 65th.

More from Yahoo Sports:

• USWNT beats Netherlands to win fourth World Cup

• Americans confirm place as greatest women’s team ever

• Masvidal needs just five seconds for UFC 239 KO

• Kawhi signing shakes up title odds in NBA