St Mirren have signed Callum Ball from Derby after he struck five goals in two trial games.

The 21-year-old has agreed a 12-month contract with the option of a further year.

The striker made 31 appearances for Derby but has more first-team experience from loan spells with Coventry, Torquay and Notts County.

Morton, meanwhile, have signed Jamie McCluskey on a one month deal. The 26-year-old is the brother of summer signing Stefan McCluskey.

He started his career at Hibs where he made his first-team debut in 2004, which made him (at the time) the youngest ever player to appear in the SPL.

He has had spells with St Johnstone, Wrexham, St Mirren, Clyde, Dundee and Forfar.