Higgins was released by Aberdeen in the summer. He is a local lad and is a big central defender, so would be decent cover.
Slack has played with Manchester City and Celtic, and can play wide right or up front, two positions we need a player for. He has also played for Republic of Ireland schoolboys, and last season helped Mossley AFC into the Unibond leagues. He also has a bit of pace, which we could do with.
All three will play in today's game against Kilmarnock at Auchencruve College. Whether they will be offered deals if they impress remains to be seen.