Middleton signed for Harrogate in June 2017 following a season in the National League with North Ferriby United.
The 22-year-old was also a member of Ferriby’s 2015/16 promotion-winning squad, having joined the Villagers after two seasons and seventy-four appearances at Scarborough Athletic.
Middleton returned to full-time football with Harrogate after spending time in the youth systems of both Doncaster Rovers and Hull City during his formative years.
He has recently returned from a month`s loan spell with Evo-Stik League Premier outfit Buxton.