It was a slow start to proceedings with Ferreira Filho Mariano, Yevhen Konoplyanka, Grzegorz Krychowiak having the only opportunities of any recognition in the first period.
Alvaro Cejudo and Heilko Westermann had decent half-opportunities at the beginning of the second-hlaf but two late goals from Gameiro and Coke secured the three points.
The bitter rivalry between the two was clear to see on the pitch as the opening proceedings of the game with a flurry of fouls but it was the home side who had the better of the chances.
The first real opportunity came in the 19th minute when Gameiro showed some great work on the wing before laying it on a plate for Mariano but his free header was well wide of the mark.
It was then the turn of Konoplyanka and Krychowiak who were only reduced to half-opportunties, the first came from the Ukranian as he looked to be in a prime position to have a decent effort on goal but it was straight down the throat of Antonio Adan.
The Pole was up next just before the halfway stage when he had an opportunity with his head but it soared well wide of the target.
The tempers reached a boiling point just after the second half began as Jose Antonio Reyes went flying in to try and get the shot towards goal but ended up catching Adan which caused tempers to fly inside the Ramon Sanchez Pizjuan.
Betis' first real attempt of the afternoon and the first of the second period as Alvaro Cejudo's wayward shot managed to find Westermann but the German defender could only turn the shot just past Sergio Rico's post.
It was then the turn of the home side once again as Gamiero looked to find Krychowiak but once again the midfielder was just wide of the mark.
Breaking the deadlock
Sevilla had the majority of the chances and they managed to break through with the opening goal in the 67th minute.
Once again it was great wing-play from the home side as the ball mader it out ex-potter Steven N'Zonzi and his cross with help of a Danial Cellabos laid it on a plate for Gameiro who head into an open net with ease for his 16th goal of the campaign.
The home side sealed the victory with ten minutes to play and the three points were sealed in some spectacular style. Coke had been quite for the majoirty of the game but managed to pull of a great individual magic as he curled in an effort from 25 yards which gave Adan no chance.
Betis attempted to grab some sort of consolation as the game began to enter it's final moments with defender Westermann. The German was looking to redeem his earlier miss when he rose highest for the corner but Rico did well to get down to keep his clean sheet.