Bacsinszky; France lost the tie 1–4. On 16 February, Cornet withdrew from the Dubai Tennis Championships because of a torn pectoral muscle. She lost to Carla Suárez Navarro in the quarterfinals of the Monterrey Open. She suffered early exits in the singles main draw of her next four WTA tournaments in Rabat (first round), Madrid (first round), Rome (second round) and Strasbourg (first round). At the French Open, she upset No. 20 seed Barbora Strýcová in the second round, No. 9 seed Agnieszka Radwańska in the third before losing to No. 28 seed Caroline Garcia in the fourth round. After the French Open, Cornet lost in the singles main-draw first round of the next five tournaments that she entered – Birmingham, Eastbourne, Wimbledon, Stanford and Toronto. She ended her five-singles match losing streak when she defeated Catherine Bellis in the first round of the Premier-5 tournament in Cincinnati before losing world No. 11, Dominika Cibulková, in the second round. In the second half of September, Cornet reached consecutively the singles quarterfinals of two WTA events – Guangzhou and Wuhan. At the Premier-5 tournament in Wuhan, she upset No. 6 seed Svetlana Kuznetsova in the second round before falling to the qualifier Maria Sakkari in the quarterfinals; that was just Cornet's third singles quarterfinal appearance in a Premier-Mandatory or Premier-5 tournament. In early October, the unseeded Cornet knocked out No. 10 seed Angelique Kerber in the second round of the Premier Mandatory China Open, before losing to her compatriot Caroline Garcia in the third round. In her last tournament of 2017 in Moscow, Cornet defeated No. 8 seed, Magdaléna Rybáriková, in the second round before losing to Natalia Vikhlyantseva in the quarterfinals in a three-hour match, meaning that Cornet advanced beyond the singles quarterfinals of a WTA tournament only once (in Brisbane) in 2017. 2018: Sixth WTA singles title On 11 January 2018, Cornet was charged by the ITF with missing three out-of-competition drugs tests that were to be conducted between November 2016 and October 2017. Under WADA rules, Cornet could face a suspension of up to two years. The case would be heard on 1 May 2018 in London. She would be allowed to play WTA and ITF tournaments until then, but if found guilty all prize money and rankings points accumulated during a certain period in 2017 would be forfeited. The French Tennis Federation stated that they would not