Colchester boss Geraint Williams has continued his clear-out at Layer Road by releasing defender Danny Granville and sending Adam Virgo and Bela Balogh back to their parent clubs.
Virgo and Balogh will now return to Celtic and Hungarian side MTK Hungaria respectively while Granville, who made 14 league starts since arriving from Crystal Palace last season, becomes a free agent.
The trio follow the four players released over the weekend by Williams as he prepares for life in League One.
Elsewhere, goalkeeper Aidan Davison has announced his retirement from football after a career spanning more than 20 seasons.
The 39-year-old former Millwall, Hull and Grimsby goalkeeper moved to Layer Road in 2004 and made 99 league and cup appearances in his time with the Us, playing an instrumental role in the club's promotion season in 2005/06.