The former Barnsley captain has recovered from serious knee injury.
Butterfield told the Pink 'Un: "It's been more than six months now, so I'm kind of used to that, sitting on the sidelines and not playing.
"It is frustrating, especially when I've just joined a new club and I want to be out there and getting myself ready for the new season and showing everyone what I can do.
"It's a bit frustrating when I'm stuck in the gym but I feel like I'm nearly there now. It's been a long time. I hope I can join in a bit in the next week or two and I hope at a push might be able to catch the last one or two pre-season games but I think that might be me being a bit hopeful."