Both players have 36-hole totals of 9-under-par 135.
In Friday's second round, Canizares gained a share of the lead with a 6-under 66, while Vanscik, the first-round leader, managed a 2-under 70, after struggling with two double-bogeys on the front nine.
"Every Spaniard wants to win this week but when you have your family here cheering on every shot, it makes it a little bit easier," said Canizares, playing in his native country. "My dad's not here (and) the key to me leading is patience."
England's Gary Lockerbie (68) is third at 8-under 136 and Switzerland's Francis Valera (67) and Jean Van de Velde (66) of France share fourth at 7-under 137.
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