England lost 4-1 to Germany in the round of 16, and ticket sales have gone slowly for the Aug. 11 friendly against Hungary at Wembley, even with the Football Association discounting prices by up to 33 percent. Sales are just starting for the opening European Championship qualifier against Bulgaria on Sept. 3.
"You see the friendlies before the World Cup, the hype is very big. Everyone is looking forward to a good campaign," Barry said. "When things don't go to plan, then you get the other end of the scale. It's up to the players and the management staff to bring the fans back. So you can understand the ticket sales being low, but the players will now want to put things right and fill the stadium back up. You do that by playing well, and getting the performances right."
England is in Group G of Euro qualifying with Bulgaria, Montenegro, Switzerland and Wales.
Barry damaged ankle ligaments playing for Manchester City on May 5 and didn't return until England's final group-stage match, against Algeria. He also started in the June 27 defeat to the Germans.
"It's been two or three weeks," Barry said. "I've had a lot of time to think about it. I'm sure the other players have."