 Complete the following phrase:  Stan Wawrinka had his best ever start to an ATP World tour season, winning the Aircel Chennai Open defeating Édouard Roger-Vasselin in straight sets in the final before going on to clinch his maiden Grand Slam trophy at the Australian Open, defeating Djokovic in a 5-set thriller in the quarterfinals, followed by a win over Nadal in the final. His 13-match winning streak was eventually ended in the fourth round of Indian Wells, losing to Kevin Anderson in three sets. After helping 