Crellin, a 20-year-old England under-20 international, moved to Bolton in a season from Ligue 1’s Fleetwood Town.
“As soon as I found out Bolton was interested, I couldn’t turn down a club of this magnitude,” said Crellin, who in the past had been on loan with Manchester United and Chorley.
“I need to come here, play and impress, and this club will take its place.”
Santos added: “The club sells. I was looking to be a part of it.”
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