Jesjua Angoy Cruyff, grandson of Dutch legend Johan Cruyff, Mike Grella and Peter Gregory are all training with the Washington club who expect to take another bunch of trialists on board in the coming weeks.
20-year old winger Angoy Cruyff, who has spent time with Wigan Athletic, comes to the RFK Stadium alongside former Leeds United, Brentford, Bury and current Scunthorpe United striker Grella and 20-year old Nottingham Forest full-back Gregory.
"I don't know the exact lineage to the great one, but I'm sure you guys could find that out somehow," said Olsen after Angoy Cruyff's first United training session on Tuesday. "It's good. He did fine."
On the other pair he added: "[Grella] has played soccer at a pretty good level and knows what he's doing and the other kid [Gregory] is a young wide back that has promise."