Andy Murray will take on defending champion Stan Wawrinka in the semi-finals of the French Open on Friday.
Wawrinka drew level with Murray on two grand slam titles after beating Novak Djokovic in the final 12 months ago. Here, we detail five facts about the 31-year-old Swiss.
1. He had an unusual upbringing
Wawrinka's parents' farm, in the hamlet of St Barthelemy near Lausanne, is also home to 75 adults with learning disabilities. Wawrinka told Swiss newspaper Le Matin: "I had a very happy childhood. I was lucky to grow up surrounded by nature and animals, to be outside all the time and to work on a big farm with my dad. By growing up at a centre for people with special needs, I learned to always fight hard to achieve what I want. In this regard, I was incredibly lucky."
2. Junior pedigree
When Wawrinka won the title in 2015, he was only the third man ever to have lifted both the senior and junior trophies at Roland Garros. The Swiss, who was the junior champion in 2003, followed in the footsteps of illustrious predecessors Ivan Lendl and Mats Wilander, becoming the first man since 1988 to do the double.
3. Tattoo inspiration
Wawrinka has a quote from Samuel Beckett's Worstward Ho on the inside of his left arm. It reads: "Ever tried. Ever failed. No matter. Try Again. Fail again. Fail better." Wawrinka told the Guardian: "I first saw the quote a long time ago. It always stayed in my mind. It's how I see life and tennis. The meaning of the quote doesn't change no matter how well you do. There is always disappointment, heartache."
4. He changed his name
Prior to the French Open in 2014, Wawrinka took the unusual step of asking for his name to be formally changed by the ATP from Stanislas to Stan. Explaining the move, he said: "Because everybody called me Stan. It's just to simplify everything on the draw, my name during press conferences. That's the only reason." Wawrinka's family name comes from his Polish origins while he has Czech grandparents and a German father.
5. The Norman effect
Wawrinka spent more than a year trying to persuade former Swedish player Magnus Norman to coach him. Norman, who reached number two in the world in 2000, had guided Robin Soderling to successive French Open finals. Since agreeing to work with Wawrinka in May 2013, the effect has been dramatic. At that stage, Wawrinka was ranked 15th and had made only two grand slam quarter-finals. Since then, he has failed to make the last eight only three times at 13 slams, won two titles and is an established member of the world's top four.