Coach Stuart Pearce suggested Wilshere had "taken his eye off the ball" after he was arrested and bailed in the wake of a late-night fracas in Kensington.
But Pearce has been impressed with the 18-year-old's reaction ahead of the must-win game against Lithuania.
"Jack has been fantastic. His attitude has been very good. I have seen more focus," said Pearce.
"Leading into the Portugal game, he was swapping phone calls with his agent and one to two other people in regards to newspaper articles which were going on.
"We just did not feel it was right to start him in Portugal. Since then, we think his focus has been much better."