Miller, pictured, stood down as Jim Harvey's number two at FC Halifax Town last week after the pair left the Shaymen following their FA Trophy triumph over Grimsby at Wembley.
The 37-year-old former Hartlepool United, Ipswich Town, Sunderland, Preston North End, Sheffield Wednesday, Huddersfield Town and Swindon Town midfielder succeeds Carl Beasley after work commitments forced Ainsley's former number two to stand down at the EVO-STIK NPL First Division North runners-up and play-off winners.
Miller, who kicked off his career with Hartlepool United before eventually going on to make 33 appearances for Sunderland in the Premier League, was appointed as caretaker-manager of Swindon Town before joining FC Halifax Town as assistant-manager in 2015.
Ainsley said: “Tommy has just come off the back of winning the FA Trophy and at 37 will also register as a player. Tommy has a wealth of professional football experience and coaching qualifications which will be invaluable this season. We are also very like-minded people who want to play the same way and I think it's the perfect match."
Miller added: “I am delighted to be joining Spennymoor. I have known Jason for a number of years and have always been impressed with the way his teams have played and the success he has had.
“Having met with chairman Brad Groves the other day and hearing of his ambitions for the club and the plans he has in place then I know it's an exciting time to be joining. With my experience and understanding of the game I am looking forward to helping the club reach its targets in moving onwards and upwards.”
Image courtesy of www.halifaxafc.co.uk
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