Oxford United have signed Alex Mowatt on a season-long loan deal from Barnsley and John Mousinho on a two-year deal after his release by Burton.
Midfielder Mowatt, 22, joined the Tykes in January on a two-and-a-half year deal and played 11 times last season.
Defender Mousinho, 31, captained Burton in all three EFL divisions before leaving the Brewers by mutual consent.
He has also played for Brentford, Wycombe, Stevenage and Preston in a career of more than 400 appearances.
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