The pint-sized Samba star, a little over 5ft 6in tall, is well aware he will face far more brutal opponents over the years - and is equally confident he can handle any rough stuff they throw at him.
Coutinho, an £8.5million buy from Inter Milan, admitted: "In Brazil, the Premier League is followed more than any other and everyone says it is the toughest competition in the world.
"The difference I've noticed already is you have to be a quick thinker and move around much sooner because the pace is so much higher.
"I need to improve my muscles because they are still quite small at the moment.
"I always knew the type of football here would be much harder but, with the help of the manager, staff and players I will try to adapt as quickly as possible.
"Of course it can be a challenge but before I came here I was well aware of the style of play here.
"To me it is a challenge and I want to deal with it as quickly as possible."