Chesterfield boss Paul Cook is expected to make a final decision on his pre-season trialists this week.
Six players turned out for the club in their pre-season win over Huddersfield Town at the weekend, including former Hull City winger Jamie Devitt.
"Jamie has got that in his locker. We're still looking at him and he's done his chances no harm," Chesterfield assistant Kevin Lynch told the club's official website.
"On the others I think there are some tough decisions that the gaffer has got to make."
Ritchie Humphreys, Matty Brown, John Shaw, Conor Clifford and Hendrick Cakin have also been training with the club this month.