Sevilla striker Freddie Kanoute was dismissed after receiving a second yellow card in the dying seconds of an action-starved first half, and it didnÃ¢â‚¬â„¢t take long for Valencia to take advantage of the extra man after the break.
Sevilla failed to clear their lines several times before young Spanish winger Mata latched onto the ball as Banega shaped to shoot, and struck a sweet left foot strike into the far corner to give his side the lead on 46 minutes.
Both sides struggled with atrocious pitch conditions Ã¢â‚¬â€œ resembling a sign of the times at the Mestalla club Ã¢â‚¬â€œ which proved almost unplayable as both sides struggled to build a passing pattern.
The away sideÃ¢â‚¬â„¢s defending bordered on shambolic during a prolonged period of pressure as Valencia searched for a second Ã¢â‚¬â€œ Mata coming close after hitting a left-footed volley just wide of the post.
Valencia goalkeeper Miguel Moya was yet to be forced into action as the game passed the hour-mark.
Brazil striker Luis Fabiano cut a forlorn figure leading SevillaÃ¢â‚¬â„¢s attack following the dismissal of his French strike partner and it was not long before he was replaced by Ivorian frontman Kone on 69 minutes.
In contrast, David Villa was causing headaches to opposition defenders by embarking on clever diagonal runs in behind on many occasions.
Valencia began to boss the game as Everton target Ever Banega controlled possession in the heart of their midfield.
Sevilla failed to produce any meaningful attacks and their desperation became clear after second-half substitute, and Ã‚Â£13 million summer arrival, Alvaro Negredo, collapsed dramatically in the Valencia box claiming an elbow by Jeremy Mathieu.
Tempers began to fray towards the final ten minutes, until the home side put the game out of sight on 80 minutes.
This time Valencia benefited from the depleted state of the pitch.
Impressive Argentine Banega dribbled passed past two defenders and spread the ball out with the outside of the boot to Pablo who hit the bobbling ball first time Ã¢â‚¬â€œ intentionally or not Ã¢â‚¬â€œ over the top of the goalkeeper and into the far corner.
Oles rang around the stadium as Los Che Ã¢â‚¬â€œ awash with confidence from the second goal Ã¢â‚¬â€œ swapped several passes.
Negredo finally forced Moya into a save Ã¢â‚¬â€œ albeit a simple one Ã¢â‚¬â€œ in the 83rd minute as he hit a low shot on the turn that drew the gameÃ¢â‚¬â„¢s action to a close.
Didier Zokora would have been left ruing his decision to leave jointly Premier League table-topping Spurs as his side slumped to defeat on a miserable night for his new club.
Valencia: Moya, Ibanez, Alexis, Bruno (Mathieu, 45), Miguel, Marchena (Abelda, 61), Banega, Pablo, Silva (Michel, 85), Mata, Villa
Sevilla: Palop, Navarro, Squllaci, Escude, Konko, Romaric (Zokora, 21), Duscher, Perotti (Negredo, 55), Jesus Navaz, Kanoute, Luis Fabiano (Kone, 69)
Man of the Match: Ever Banega Ã¢â‚¬â€œ Instrumental in build-up to both goals and rarely wasted possession on an appalling surface.
The weekendÃ¢â‚¬â„¢s other La Liga results:
Real Madrid 3-2 Deportivo
Zaragoza 1-0 Tenerife
Athletic Bilbao 1-0 Espanyol
Mallorca 2-0 Xerez
Osasuna 1-1 Villarreal
Racing Santander 1-4 Getafe
Malaga 3-0 Atletico Madrid
Almeria 0-0 Valladolid
Barcelona v Sporting de Gijon (31 Aug, 21:00)
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