Mirra Andreeva jokingly branded her opponent a "b****" after losing a heartbreaker at the Ningbo Open.

The 17-year-old suffered a three-set defeat to Daria Kasatkina in Sunday's final. Andreeva recovered from a bagel set to force a decider but Kasatkina ultimately won 6-0 4-6 6-4.

After having a day to process her defeat, Andreeva shared an unusual social media post to sum up the final.

Andreeva was looking to end her season on a high after reaching her second career final on Sunday at the WTA 500 event in Ningbo. The teenager had already won her maiden title in Romania over the summer and was hoping to add to her trophy cabinet.

But experienced fifth seed Kasatkina got the better of her, winning her second title of the season and returning to the world's top 10.

Andreeva has now reflected on her time in Ningbo in an Instagram post, where she had some choice words for her opponent. "Ending my 2024 season with the final in Ningbo!" the world No. 17 wrote.

"Congrats to this b**** @kasatkina , you definitely showed some great tennis," she joked, adding an eyeroll emoji and a crying face.

The Russian also had a message for her coach, former Wimbledon champion Conchita Martinez. She added: "And sorry Conchita hope you don’t kill me:)".

Kasatkina has yet to see the post but world No. 43 Caroline Garcia left a comment. "Congrats on a great season Mirra," she wrote. "love the Conchita/Mirra energy! You are making a great team, it’s really nice to witness."

Despite her social media post, Andreeva and Kasatkina have a close bond. And the world No. 9 was quick to comfort the 17-year-old when she was left in tears on Sunday.

Andreeva struggled to get through her speech and began crying as she congratulated her opponent. Kasatkina raced to the stage to embrace her compatriot, consoling her before Andreeva continued speaking.

Addressing Kasatkina and her box, the teenager said: "You guys have done an amazing job throughout this week and as well throughout the whole year.

"I know you've been playing a lot of finals and finally at the end of the year you have the title so I didn't want to say like in a bad way but you really deserve to win and congrats to you and all of your team."