quarterfinals where she faced Petra Kvitová. She lost to the Czech in straight sets. At the Luxembourg Open, Vinci the sixth seed easily defeated Tereza Smitková in the first round but then lost to Beck in straight sets. Vinci and Errani once again qualified for the WTA Finals as the top seeds. They were forced to retire in their first hurdle to Květa Peschke and Katarina Srebotnik due to an injury suffered by Errani. Vinci ended the season outside the top 40 for the first time since 2010 at No. 49. 2015: Grand Slam finalist Vinci kicked off her 2015 season by playing at the Auckland Open. She lost in the first round to seventh seed CoCo Vandeweghe, 7–5, 2–6, 3–6. The following week, she played at the Hobart International. Seeded ninth, Vinci made it to her first quarterfinals of the year defeating wildcard Olivia Rogowska and Annika Beck. In the quarterfinals, she fell to eventual champion Heather Watson in two sets. At the Australian Open, Vinci overcame Bojana Jovanovski to reach round two but lost to tenth seed Ekaterina Makarova, 2–6, 4–6. Seeded third at the Rio Open, Vinci was upset in the second round by qualifier Verónica Cepede Royg, 6–2, 6–3. She then retired in her first-round match against Kiki Bertens at the Mexican Open with a shoulder injury. Vinci exited the second round at the Indian Wells Open to 24th seed Sabine Lisicki, 6–1, 5–7, 6–4. The following week at the Miami Open, she dropped her opening match against qualifier Tatjana Maria, 6–7, 3–6. During the week, it was also announced that Vinci and her long-term doubles partner Sara Errani decided to discontinue playing doubles together. They issued a joint statement stating that they had decided to pursue more in their singles career. Beginning her clay-court season seeded sixth at the Morocco Open, Vinci lost to fellow Italian Karin Knapp in the second round, 7–6, 2–6, 2–6. She then posted good results at the Madrid Open. She reached the fourth round for the second year in a row beating Monica Puig and Alizé Cornet. She ended up losing in the fourth round to 13th seed Lucie Šafářová, 4–6, 7–6, 0–6. Ranked 44 at the Italian Open, Vinci was defeated in the first round by world No. 41, Heather Watson, 6–3, 6–1. Seeded fourth at the Nürnberger Versicherungscup, she reached her first final of the season but came