Federer won his first non-official title in 2001 when partnering Hingis at the Hopman Cup and has since gone on to win more Grand Slam titles than any other player in history with 19.
The run started by winning the 2003 Wimbledon title and he has continued his success by winning both the Australian Open and Wimbledon in 2017, and Hingis says she has helped him on that journey.
She said: "I always say I taught him how to win his first tournament. We ended up winning Sydney too, the week after. There were some great moments we shared. We all know what happened afterwards."
Federer and Hingis were due to be doubles partners in the 2016 Rio Olympics, but injuries prevented him from playing in that tournament and the rest of the 2016 season. However, he has dramatically recovered his form to win two of the Grand Slam events this season.