From winning the UEFA Champions League in his first full season as a professional footballer to lifting the Premier League Trophy for Manchester United, Owen Hargreaves experienced great highs during his playing career.
But speaking in the sixth part of "Inside Matters", a series of exclusive interviews with football stars about the mental challenges they have faced, Hargreaves says his success made it all the harder when he had to come to terms with the reality of early retirement.
"As blessed as I was to be able to play football, it felt like it was taken away from me, which was almost the hardest part because there wasn't something I could do to get it back," says Hargreaves of the injury problems that forced him to retire in 2012 while on the books at Manchester City.
"It broke my heart. There were days where I just couldn't understand how I got there."
"There were days where I just couldn't understand how I got there. But in the end, I did. There was no point in living in the past."
Hargreaves was just 31 when a long-term knee injury eventually meant he struggled to even get up and down the stairs in his own house.
For an athlete once at the top of the game he struggled to overcome his sadness. But eight years later and now working as a pundit, he has learnt to cherish the memories he made.
"In the end, I did [come to terms with it]," he explained.
"There was no point in living in the past. My football career was beautiful to start, it finished not how I wanted, but it was gone.
"All those experiences good and bad are just part of anyone's life. The good was amazing and the bad was probably worse than I could have expected.
"You can't replace playing in front of 75,000 fans at Old Trafford. I don't have any of my football stuff in my house - trophies, medals shirts - because I didn't want to be reminded of the beautiful stuff I was able to do.
"I put it to the side and said, 'that book's over, time to start a new chapter'."