Canales, on loan from Real Madrid, struck a low shot from 25 yards (meters) that skidded into the far corner in the fourth minute.
The win lifted Valencia to 13 points, one ahead of Real Betis, which hosts Levante on Sunday. Malaga can draw level with Valencia atop the standings with a win in the late match Saturday against Getafe.
Also Sunday, Barcelona visits Sporting Gijon and Real Madrid travels to Espanyol.
In other Saturday results, Hernan Lopez’ late header earned Villarreal a 2-2 draw against Zaragoza, Osasuna had a 2-2 draw at home against Mallorca, and Racing Santander drew 1-1 with Rayo Vallecano.
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