World number three Stan Wawrinka believes Andy Murray has thoroughly merited his spot as number one in the world and admits he will be "tough" to beat heading into the ATP World Tour Finals in London next week.
The Swiss number one has been drafted into the same group as the Scot -- accompanied by fifth-seed Kei Nishikori and seventh-seed Marin Cilic -- and says he will need to ensure he is at the top of his game if he is to upstage Murray's coronation in the English capital.
Praises the Scot's mentality
Wawrinka has garnered a reputation as a big-match player since he stamped his authority on the tour with his Australian Open triumph over Rafael Nadal in 2014 and believes Murray boasts the mental fortitude to handle the pressure as the number one player on the planet.
"He did really well with the pressure, he won Wimbledon this year and he won the Olympics in London, so he knows how to deal with it," the 31-year-old told reporters at a Yonex event in London's Carnarby Street.
The Swiss also says Murray is the man to beat after his recent surge in form, claiming titles in Beijing, Shanghai, Vienna and Paris.
Wawrinka was also questioned as to whether he believes he could shatter the so-called big four's dominance in the near future and become world number one, but the Swiss was candid, hinting at a desire to discover more consistency throughout the year and concedes he is "way off that".
However, the number three seed is proud of his status among the top three players on the tour, saying: "I'm number three, in the top four for the last three years, so it's already something really special."
The World Tour Finals commence at the O2 Arena in London on Sunday.