Tottenham Hotspur defender Walker was ruled out of the tournament in Brazil due to a pelvic injury after starting five of the World Cup qualifiers.
He would likely have vied with Glen Johnson to be Roy Hodgson’s first choice at the World Cup, where England exited at the group stage.
Walker is now back in action after playing in Spurs’ pre-season friendly against Toronto FC in midweek and the 24-year-old is determined to make up for his World Cup heartache.
“It was good to get 45 minutes on the pitch again pain-free. It is a step in the right direction,” Walker told The Sun.
“Being injured for so long and missing out on the World Cup has been the most difficult part of my career.
“Roy just said he couldn’t really take a risk with me. It was hard to hear. But I knew I wasn’t playing for my club at the time, so I had to take it on the chin.
“It hurt a lot, but hopefully that pain can help me develop even more as a player. This has taught me that things do not always go your way in football.
“Sometimes you are left down in the dumps. And there is nothing you can do about it, other than get back in the gym, or on the training field to work hard on trying to get fit again.
“It was the manager’s decision and you have to respect it. I will try to get back into the squad and then on that team-sheet again. I hope to be England’s right-back for many years to come.”