Midfielder has had two spells with Stevenage, including one on loan at the end of last season
John Mousinho has signed for Burton Albion.
The midfielder, who had a second spell at Stevenage last season on loan, was released by Preston North End in the summer and has now signed for the Brewers.
The former Wycombe Wanderers man said on the last day of the season that he would be willing to listen to Boro should they want to bring him back to the club he left in 2012 on a permanent deal.
However, the 28-year-old has now signed for Stevenage’s League 2 opponents on a two-year deal.
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