The Blues are taking two more players on trial, Dutch striker Iwan Redan and French defender Delis Ahou. Former QPR and Burley defender Arthur Gnohere is already at the club hoping to win a deal.
Redan, previously with Sparta Rotterdam, Vitesse, RBC Roosendaal, RKC Waalwijk and JC Roda, plays wide on the left as well as up front. The 25-year-old is currently a team-mate of Martijn Reuser at Willem II and has scored 26 goals in 95 appearances in the Dutch top division although he is currently out of favour at the Tilburg club.
Preston North End and Sheffield Wednesday have previously taken Redan on trial with Paul Sturrock at one stage keen on signing him on loan in January.
Ahou is a 21-year-old left-back who has previously played with Nantes and Carquefou. He is now with Ajaccio GFCO who are currently bottom of the equivalent of League One in France.
Joe Royle told the club site: "Our chief scout Colin Suggett has been working hard at bringing in players on trial and we have been talking to contacts, clubs and agents to see what players are out there."
Both players are available on free transfers.