"I remember when I was a young player at CSKA Sofia and the good life was all I was interested in. Celtic came in for me and I moved to Glasgow, to another country, to a new world. I didn’t speak the language and I thought it would never happen for me. I knew nobody.
Fortunately, I met people who helped me to turn my life around. I came to know great teammates who showed me the proper way, the way I had to be if I was going to be a serious professional and compete at a high level.
I came to appreciate so much the opportunity to work with that level of professional people because it made me something like them.
At Celtic Football Club and at Aston Villa Football Club I was privileged to live a life competing at a high level and playing the game I love, supported by the most passionate fans."
Stiliyan Petrov says knowing he is ready for new challenges will make it easier to move on from football:
"Since being diagnosed with acute leukaemia in March 2012, I have come to understand and appreciate the way in which this disease impacts the lives of so many people.
I can help and I want to help and, in setting up a foundation to help address the issues involved when people are diagnosed with this illness, I hope to make a difference.
This will be my new challenge, one I will face with all the enthusiasm, energy and drive with which I have faced every single challenge."
"I’ve never been a person for making grand statements. I’ve only ever got on with my job, while remaining grateful to have great team-mates, great people around me and, most of all, a fantastic family.
They have been powerful pillars of support when I have needed them most over the past year.
To my wife, Paulina, and my sons, Kristiyan and Stiliyan, I love you very much and I will always for your constant love and support.
Also to my mum and dad, my brother and Paulina’s mum and the people who have been closest to me throughout this time – you know who you are and I love you all.
Each and every day I thank God for giving me the opportunity to still be with my family.
Football has been the other great love of my life, so it is with a heavy heart that I am announcing my retirement from the game.
The emotions are overwhelming really, but the continued support of family, friends and the great people I have come to know will make it easier for me to move on from the only life I’ve ever known."
Aston Villa captain Stiliyan Petrov, who has been suffering from acute leukaemia, has announced his retirement from football on the club's website.
Writing on the club's website, the Bulgarian said he would be starting a foundation to help people diagnosed with the disease.
"That I am ready to embrace new challenges will make this process much easier," he said.
"Since being diagnosed with acute leukaemia in March 2012, I have come to understand and appreciate the way in which this disease impacts the lives of so many people."
"My leukaemia is now in remission and I have finished my high intensity treatment," he added.
Aston Villa captain Stiliyan Petrov has announced his retirement from football after a battle with leukaemia.