As a way of reflecting on the year, a crew of WTA players opened up letters to themselves from the past. They had written secret notes at Indian Wells in March and then read them out loud at the end of 2018.

Caroline Wozniacki, Karolina Pliskova, Simona Halep, Caroline Garcia, Angelique Kerber and Petra Kvitova all took part.

Wozniacki, who had won the Australian Open just a few weeks earlier, had a great note to open: "No matter what happens the rest of the year you year is already successful on court so enjoy the rest of the year, take in the moment and just have fun."

The Dane did a solid job of enjoying her season after securing that maiden Grand Slam title and returning to No. 1.

Kvitova had a lesson to read: "Don’t think too much and be more relaxed on the court and enjoy being out there." She thinks she did a pretty good job of it.

Pliskova was so jarred by what she found in her envelope that she was pretty sure she never wrote it (but there was video proof that she did):  "You were amazing this year, but keep practicing."