The 20-year old Reds defender spent three months on loan at the KC Stadium last term and impressed enough for the Tigers to enquire about whether a return is possible and Pearson hopes it is.
"I never rule anything in or out but I would say it's unlikely," Pearson told the Hull Daily Mail regarding a move prior to this weekend's Championship opener.
"Ayala is a target and we've put a bid in. The clubs are in discussion and we'll see where it takes us.
"As always the criteria of how you add to your squad is governed by finances but we'll always try and bring in the best players that are available to us."