Sergio Aguero insisted his retirement is not a tragedy as he looked back on an outstanding career that taught him to "turn defeat into victory".

The former Manchester City and Barcelona forward announced his retirement on Wednesday after suffering from a heart problem.

Aguero struggled with chest discomfort and dizziness, which were later attributed to a heart arrhythmia, in Barcelona's 1-1 draw with Deportivo Alaves on October 30.

After consultation with specialists, Aguero – who is City's leading scorer in Premier League history – accepted he would not be able to play again as the risk to his health would be too great.

But despite his sudden retirement, the 33-year-old insisted he would look back on his "amazing career" fondly as he reflected on the lessons football has taught him.

"I've always known that I'd give it all to have a chance to play again," Aguero said in his statement published on Twitter. However, after the last exams, I was advised by my doctors to cease practising professional football.

"Their words were sufficient to make a choice. Retiring under these circumstances is difficult, but life comes first - I've known that from the start.

"One of the many things that football taught me is that you can turn defeat into victory. This won't be any different. It's surely painful but it's no tragedy.

"A tragedy would have been another thing altogether. My thoughts are not on the time I could have played on, they are on the wonderful 18 years I did get to play.

"This amazing career will remain with me, and so will carrying it out with passion and dedication year after year. I keep the affection and care I received from each of the teams I played for when I was just a kid.

"And then at Independiente, Atletico Madrid, Manchester City, Barcelona, and Argentina's national team, always so dear to me. My recognition goes to the fans, who stood by me through thick and thin - your support has made me stronger."

Aguero goals

Aguero left City for pastures new at Barcelona on a free transfer in July, having scored 184 times in the Premier League at a rate of one every 108 minutes, the best frequency of any player to net at least 20 in the competition's history.

Indeed, the former Argentina international could play another 2,520 minutes of Premier League action (the equivalent of 28 full games) without scoring, and he would still boast the best minutes-per-goal ratio of any player to have scored 20 or more times.

Aguero is also the Premier League's highest-scoring overseas player and holds the record for the number of goals scored for one club, while his 12 hat-tricks are another benchmark in the competition.

But as his career comes to an end, the former Atletico Madrid man heaped praise on those he has worked with.

"I want to thank all the trainers, team-mates, colleagues, staff, physios and managers who allowed me to develop my career in the best of conditions," he continued.

"My special gratitude goes to my family and friends, who were always by my side. And to my agents, the same I've kept since I was 14 years of age, who accompanied me with utmost professionalism and honesty.

"Beyond the titles I've contributed to win - something I greatly value - my biggest achievement has been earning the respect of my colleagues, and the love from the world of football.

"That's something that won't change - I'll keep it in my heart and it will make me strong for what's to come.

"Life goes on, and there's plenty of it ahead. It will be a new stage, a different one indeed, but I'll keep on just like I've done so far: always positive, with enthusiasm and joy."