Valencia beaten in ugly clash at Sevilla
Valencia finished with 10 men after Aritz Aduriz was sent off for stamping on the foot of Emir Spahic with around 20 minutes left.
Sevilla midfielder Piotr Trochowski and defender Julien Escude were dismissed in the 57th and 68th minutes respectively.
Sevilla's 34-year-old striker Frederic Kanoute galloped on to a Jesus Navas pass to put the home side ahead in the 18th minute at the Sanchez Pizjuan, before Banega struck his 69th-minute spot-kick against the post.
The referee had awarded the penalty after Escude felled Aduriz when he was clean through on goal and was shown a straight red.
Sevilla climb to second on 11 points from five games, one ahead of third-placed Valencia and one behind surprise leaders Real Betis, Sevilla's promoted city rivals who play at Getafe on Monday.
Athletic Bilbao's new coach Marcelo Bielsa is still without a win this season after his side drew 1-1 at home to Villarreal.