24-year old Fernandez has joined the Whitecaps on a year-long loan with the view to a permanent deal while 22-year old Mezquida has been transferred - both players coming from homeland club Boston River.
Both midfielder/forwards will join Vancouver pending receipt of their International Transfer Certificates, Canadian work permits and visas. Per Major League Soccer and club policy, terms of the contract were not disclosed.
"Sebastian and Nicolas are exciting young attacking players with a lot of potential," Whitecaps FC head coach Carl Robinson said in a statement.
"Both players like to play with the ball on the ground and are not afraid to attack defenders one-on-one with pace."
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