Mansfield born, Broadhead started his career at Chesterfield gaining experience of the Evo-Stik League with loan spells at Buxton, Worksop, Matlock and Frickley. In 2015 he was released by Chesterfield and joined Mickleover Sports, where he made 32 appearances in the Premier Division. On deadline day in 2017 he joined Boston United. Jack spent the majority of last season at AFC Mansfield.
The Gingebreads Paul Rawden "We're looking for players that have got the experience and knowledge of being in this division. Jack has that having had numerous spells at different clubs. We all know it's a very tough competitive league. Jack is tall lad, he's strong in the air and is known to pop up with a goal or two from corners. Something we lacked last season."
Jack added "I'm really pleased to sign for the club. Grantham are a big club and I was delighted to get the call from Paul. He's explained what he wants from the squad and how we need to get to up to speed very quickly. I'm looking forward to getting to know everybody at the club and hearing the supporters I've been told about!"