Halep took another big hit during her rocky 2015, losing in the first round of Wimbledon to 22-year-old Jana Cepelova in three sets.

The first round of the 2015 Wimbledon almost passed without any drama. Then late in Day 2, the tournament got its first shocker. Women’s No. 3 seed Simona Halep fell in three sets — 5-7, 6-4, 6-3 — to unseeded Jana Cepelova, currently No. 106 in the world. Halep, 23, is a rising star in women’s tennis, making the final at last year’s French Open and the semifinals at Wimbledon. On Tuesday, however, she was bested by an even younger up-and-comer.

The difference was unforced errors. Cepelova committed just 20 to Halep’s 34. The swing was palpable in a match in which Cepelova won just six more points — 98 to 92 — than her favored opponent. After committing six double faults in the first set, Halep tried to dial back her second serve, but the result was losing 17 of her 21 second-serve opportunities over the final two sets.

Though Halep hasn’t had the strongest 2015, she was considered one of the favorites to potentially knock Serena Williams off her throne overseeing women’s tennis. This loss coupled with a second-round exit at Roland Garros should leave Halep scrambling to gather whatever is left of her 2014 mojo before the end of August when the U.S. Open begins.

Elsewhere, the day passed without much fanfare. Petra Kvitova, Roger Federer, Andy Murray and Rafael Nadal all won in straight sets over unseeded foes. Men’s No. 13 Jo-Wilfried Tsonga advanced as well, but with much more trouble. He needed three hours and 51 minutes to finally lay Luxembourg’s Gilles Muller to rest, 7-6 (8), 6-7 (3), 6-4, 3-6, 6-2.

On to Round 2 beginning Wednesday, when the intensity and intrigue should ramp up. Match results featuring ranked players below:

Men’s singles

No. 2 Roger Federer def. Damir Dzumhur, 6-1, 6-3, 6-3
No. 3 Andy Murray def. Mikhail Kukushkin, 6-4, 7-6 (3), 6-4
No. 10 Rafael Nadal def. Thomaz Bellucci, 6-4, 6-2, 6-4
No. 12 Gilles Simon def. Nicolas Almagro, 6-4, 6-4, 7-5
No. 13 Jo-Wilfried Tsonga def. Gilles Muller, 7-6 (8), 6-7 (3), 6-4, 3-6, 6-2
No. 15 Feliciano Lopez def. Steve Darcis, 6-2, 7-6 (4), 6-4
No. 18 Gael Monfils def. Pablo Carreno Busta, 6-4, 6-4, 7-5
No. 20 Roberto Bautista Agut def. Ruben Bemelmans, 6-1, 6-3, 7-6 (6)
No. 22 Viktor Troicki def. Aleksandr Nedovyesov, 6-1, 6-4, 3-6, 6-3
No. 23 Ivo Karlovic def. Elias Ymer, 6-7 (2), 6-2, 6-4, 7-6 (2)
No. 25 Andreas Seppi def. Brydan Klein, 6-3, 6-2, 6-2
Pablo Andujar def. No. 29 Guillermo Garcia-Lopez, 3-6, 6-4, 3-6, 7-5, 6-4
No. 30 Fabio Fognini def. Tim Smyczek, 6-4, 6-3, 6-2
Sam Groth def. No. 31 Jack Sock, 6-3, 3-6, 6-3, 6-3

Women’s singles

No. 2 Petra Kvitova def. Kiki Bertens, 6-1, 6-0
Jana Cepelova def. No. 3 Simona Halep, 5-7, 6-4, 6-3
No. 5 Caroline Wozniacki def. Saisai Zheng, 7-5, 6-0
No. 8 Ekaterina Makarova def. Sachia Vickery, 6-2, 6-4
No. 10 Angelique Kerber def. Carina Witthoeft, 6-0, 6-0
Ying-Ying Duan def. No. 12 Eugenie Bouchard, 7-6 (3), 6-4
No. 13 Agnieszka Radwanska def. Lucie Hradecka, 6-3, 6-2
No. 15 Timea Bacsinszky def. Julia Goerges, 6-2, 7-5
No. 17 Elina Svitolina def. Misaki Doi, 3-6, 6-3, 6-2
No. 18 Sabine Lisicki def. Jarmila Gajdosova, 7-5, 6-4
No. 20 Garbine Muguruza def. Varvara Lepchenko, 6-4, 6-1
No. 25 Alizé Cornet def. Ana Konjuh, 6-2, 6-2
No. 26 Svetland Kuznetsova def. Laura Siegemund, 6-3, 6-4
No. 28 Jelena Jankovic def. Elena Vesnina, 6-4, 3-6, 10-8
No. 31 Camila Giorgi def. Teliana Pereira, 7-6 (4), 6-3
Heather Watson def. No. 32 Caroline Garcia, 1-6, 6-3, 8-6