Argentinian defender Gabriel Mercado was the hero for Sevilla as they secured a 1-0 win over city rivals Real Betis on a night of controversy at the Estadio Ramon Sanchez Pizjuan.
The summer signing from River Plate decided a frenetic and often overly physical encounter when he deflected home a Samir Nasri free-kick in the 51st minute.
It took Sevilla up to second in LaLiga as they continued an encouraging start to life under Jorge Sampaoli with three wins and two draws from their five matches.
But Betis coach Gus Poyet had every right to feel aggrieved as what should have been a quickfire equaliser for Alex Alegria was wrongly ruled out for offside against Ruben Castro.
The derby began in typically frantic fashion as Betis' Brazilian midfielder Petros was booked after 30 seconds for a late lunge on Vicente Iborra, before German Pezzella was also yellow-carded for the second of two ugly challenges, the first on Steven Nzonzi and the second on Franco Vazquez.
Sergio Escudero fired a left-foot shot high over the bar after 15 minutes when the ball broke to him, and another flashpoint erupted moments later when Bruno went in with a head-high challenge on Luciano Vietto.
Vazquez headed high over the top after good work from Escudero down the left as Sevilla tried to impose some rhythm on a disjointed match.
Betis began to look brittle at the back as Vietto seized on an error to get behind Bruno down the left but his shot was charged down by Petros, and more hesitancy -- this time from Italian defender Cristiano Piccini -- meant goalkeeper Antonio Adan had to charge down a Nasri shot immediately afterwards.
Piccini made amends to smartly deny Escudero a header on goal from Vitolo's cross on the half-hour mark, before the game descended into another niggly period. Nasri was lucky not to be sent off for a crude challenge on Felipe Gutierrez with five minutes of the half remaining, having been booked earlier.
The breakthrough came six minutes into the second half as Nasri floated the ball into the box and Mercado got himself in front of Adan and the merest of touches off his back was enough to alter the flight of the ball sufficiently to deceive the goalkeeper.
Betis thought they had scored an instant equaliser but Castro was wrongly given offside as he latched on to a deft chip from Darko Brasanac before he swept the ball across the six-yard box for Alegria to tuck in.
Sevilla goalkeeper Sergio Rico was called into action for the first time in the 65th minute to parry wide a shot from Castro which bounced awkwardly in front of him, with the visitors enjoying their best spell of the game.
Vazquez came close to a second for Sevilla as his left-foot shot curled agonisingly wide with 20 minutes to go, and Pablo Sarabia avoided a straight red card for going in studs-up on Petros.
There was time for Castro to have one last attempt a minute into stoppage time after he received the ball from substitute Charly Musonda, but Rico held onto it.