Article:BBC Radio Sheffield understands that the 22-year-old has signed a three-year deal with the Championship side.
He could make his debut in Saturday's season-opener with MK Dons.
"Last season he was outstanding and I am led to believe he swept the boards for every Peterborough United player of the year award that was on offer," boss Steve Evans told the club website.
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A summary of the above article is?
Rotherham United have signed Peterborough United midfielder Joe Newell for an undisclosed fee.