Berahino was on the mark in WBA's draw with Manchester United.
Peace said: "Saido was thrust into it last season. He's been through quite a sharp learning curve over the last year but he's come back a changed boy.
"You see him praying before games. Somebody's said to him: 'If you want to get on, you've got to focus.' Chalk and cheese from last season. He let himself be a bit misled.
"It's brilliant for us having somebody coming through our academy into the first team."
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