Thigh muscle injury

Hi,
I have had this problem for a couple of years now.

I play football and the problem is with my right thigh when kicking the football.
I get a pain in my thigh which is really painful when kicking the ball with any power. For the first 10 minutes it means I cant kick the ball with any power at all. After the first 10 minutes the pain eases slightly, but I still cant kick the ball with more than 50% of what I used to due to the pain.

The problem only lies when kicking the ball. I do not feel any pain at another time either when I walk/run and stretch.
I have rested the thigh many times, but the pain still persists.
Can anyone give me advice on what the problem is and what I can do about it. I have tried to strap the thigh and use deep heat, but nothing stops the pain.

I would be grateful for any help.

Thanks