Celtic number two Johan Mjallby has confirmed the club have taken on Milos Lacny and Katlego Mphela on trial.
Lacny, 23, actually had a trial with The Bhoys two years ago, but he opted to join Sparta Prague.
He has since slipped down the Czech side's pecking order and now Celtic are once again looking at the Slovakian.
Joining Lacny at Parkhead is South African Mphela, who was interesting arch-rivals Rangers last summer.
Mjallby is looking forward to seeing the pair up close and personal and hopes they can express themselves while at the club.
"We have a guy from Slovakia and a South African on trial," confirmed Mjallby. "It's good to get them in to see what they offer.
"It is hard when you come in on trial because you don't know the players or surroundings but it is up to them to express themselves."