Britain's Francesca Jones has said she tries to use her congenital syndrome as a positive after making it through to the main draw of the Australian Open on Wednesday.
The British No 5 has three fingers and a thumb on each hand, three toes on one foot and four toes on the other.
Despite the condition, she booked her place at the Australian Open with a resounding 6-0 6-1 victory over China's Lu Jia-jing in the final round of qualifying.
"I wouldn't say I've ever reached a low point due to my syndrome. I stand by what I've said previously which is I try and use it as a positive and I see it as an advantage in many ways," said Jones, who has had over 10 surgeries in her life already.
"I've definitely had to work a lot more on my physicality.
"Personally my challenge has been to put myself in a physical shape that prevents injuries. My feet work in a different way and that means I run differently, my balance goes through my feet and my toes in a different way.
"For sure, I've always had a small grip and a really light racket and I am hesitant to change that because it's worked well so far. I guess in the gym I've spent a lot of time trying to gain strength to support my muscles that can maybe support the weaknesses that I may have."
The 20-year-old from Bradford overcame a finger injury and a "wee mental breakdown" to reach the main draw of a Grand Slam for the first time.
She said: "Before the first few days before my match, I was speaking to my coach and I was saying that my fingers had actually split from the cold in the UK and I couldn't hold the racket too well on my forehand side.
"The forehand is my best shot so I had a wee mental breakdown before the match to be honest. It was a few days before the match and my fingers were still cut and I wasn't sure how I'd be able to take advantage of my weapon.
"I think I was probably well prepared in terms of physically and mentally because I had a lot of time during pre-season and we worked really hard.
"I tried to trust the work that we did but I am quite a perfectionist so I do worry about the days that I didn't hit the forehand exactly the way that I should have done or I wasn't serving well."
- Tiley: We will get everyone to Melbourne
- Download the Sky Sports Scores App: Apple | Android
- The UK's No 1 scores app: Find out more
Jones is still based in Barcelona, but also trains at the National Tennis Centre in Roehampton as part of the support offered by the Lawn Tennis Association's Pro Scholarship Programme.
She will now board a chartered flight to Melbourne where the players will serve a mandatory 14-day quarantine before warm-up events start on January 31 before the Australian Open.
Don't forget to follow us on skysports.com/tennis, our Twitter account @skysportstennis & Sky Sports - on the go! Available to download now on - iPhone & iPad and Android