Within days of that defeat Lansbury agreed a loan deal with West Ham after spurning the chance to stay in the Premier League at Swansea.
Then he scored two goals, shining for the England Under-21s in a 6-0 crushing of Azerbaijan.
"Coming with England helped clear my mind," said Lansbury who will again be in action for Stuart Pearce's hopefuls at Barnsley against Israel tonight.
"You can't replicate first team football. Reserve-team football doesn't mean much compared to first team. First-team football gives you a cutting edge."