Federer and Wawrinka met again at the US Open in 2015, when Federer claimed a 6-4, 6-3, 6-1 victory over his compatriot in the quarterfinals (going on to finish runner-up to Djokovic) to improve to 17-3 lifetime against Wawrinka.
The Swiss superstars then squared off at the Barclays ATP World Tour Finals in 2015, 12 months after their gripping, controversial meeting at the same stage in 2014. Federer claimed a 7-5 6-3 victory- his fifth victory in six matches against his compatriot.
The most recent meeting between the pair came at the 2017 Australian Open, with Federer withstanding a mid-match fightback from Wawrinka to emerge triumphant in a thrilling 7-5 6-3 1-6 4-6 6-3 semi-final victory. Both players battled knee problems towards the end of the encounter, but it was Federer who finished stronger, claiming the memorable five-set triumph and going on to win his 18th grand slam title by beating Rafael Nadal in another five-set thriller in the final.
Federer and Wawrinka at the 2017 Australian Open (Photo by PAUL CROCK/AFP/Getty Images)
They are due to face off for the 23rd time in the Indian Wells final on Sunday from 1.00pm local time/ 8.00pm GMT.