He is now set to become one of the shortest centre-halves in the Premier League at 5ft 10in tall.
Mariappa told the Reading Chronicle: "Like most people I tried every kind of sport as a kid.
"I was really into judo before I even started playing football. Then as a teenager I was quite into basketball which is where I think I got my leap from.
"I also did athletics and I think the combination of all those sports helped me in my football career.
"But if I had to say one in particular it was basketball. I can really get some good height when I jump, and I can use to good effect."