The BNP Paribas Open in Indian Wells commenced today, Beijing time. This tournament is often hailed as the "Fifth Grand Slam" and is also the first Masters 1000 event of the year.
Coupled with the Miami Open, which follows immediately after, these two tournaments are collectively known as the Sunshine Double. Winning both titles in a single season is called completing the Sunshine Double, a highly prestigious achievement in tennis.

Has anyone in history accomplished this? Yes, and quite a few have. Eleven players have managed to win the Sunshine Double in a single season, but achieving it multiple times is exceedingly rare. Only three players in history have done so multiple times: Steffi Graf, Roger Federer, and Novak Djokovic.
The German legend has long been one of the record-setters in women's tennis and was also the first female player to complete the Sunshine Double. After achieving the Calendar Year Golden Slam in 1988, the enduring Graf first captured the Sunshine Double in 1994 and then repeated the feat in 1996.

Swiss maestro Roger Federer has a long and storied history with the Sunshine Double, winning it three times. This includes consecutive triumphs in 2005 and 2006. In 2017, experiencing a career resurgence, he again defeated his longtime rivals Stan Wawrinka and Rafael Nadal to secure back-to-back titles, making him the most recent male player to achieve this.
In fact, during the years following his second peak, Federer performed well at the Sunshine Double annually. In the 2018 Indian Wells final, he lost to Juan Martín del Potro, granting the Argentine his sole Masters 1000 title. In 2019, he was defeated by Dominic Thiem, who also claimed his first and only Masters trophy. However, Federer went on to defeat John Isner at the Miami Open that year, securing his final Masters 1000 championship and his last significant title.

The "record collector" Novak Djokovic holds the all-time record with four Sunshine Doubles. He first claimed it during his initial peak year in 2011 and then achieved a remarkable three-peat from 2014 to 2016.
In recent years, Djokovic, who has streamlined his schedule, often opts to play Indian Wells while strategically skipping Miami. Firstly, at an advanced age, the back-to-back grind is physically taxing. Secondly, with the European clay season commencing shortly after Miami concludes, there's limited time for optimal preparation and adjustment. However, Djokovic has made early exits at both events in recent years. Riding the momentum of another deep Grand Slam run this season, can he rediscover success at the Sunshine Double?(Source: Tennis Home, Author: Luo Cheng Qi Ye)