The hosts took just two minutes to take the lead through Ruben Casto's penalty, but the visitors equalized shortly before the break before the Betis goalkeeper saved the point.
The hosts had taken the lead after just two minutes when Ruben Castro fired home from the spot after Salva Sevilla was felled by Gorka Iraizoz. Aritz Aduriz equalized shortly before the interval, and Marcelo Bielsa's side can consider itself unlucky not to have claimed all three points in Andalusia after the Betis goalkeeper came up big to force the draw.
Betis went into the encounter in high spirits after the 2-0 win over Levante, and it wasted no time in making its mark against an inconsistent Bilbao side. Iraizoz inexplicably rushed from goal and took out Sevilla, allowing Ruben Castro to fire high into the top corner from the penalty spot shortly after the opening whistle.
Bilbao began to grow into the match, and Adrian made his first impressive save of the night when he parried Ander Herrera's stinging drive from the edge of the area, before Iker Muniain's clever run and shot was blocked by Marco Amaya.
Shortly before the break, the visitors found themselves on level terms, as the excellent Herrera picked out Aduriz with a superb pass, allowing the striker to lift the ball over the on-rushing Adrian and into the net.
Bilbao started the second half as impressively as it finished the first, but Betis carved out the first meaningful chance of the second phase, when Amaya somehow contrived to send his effort wide when unmarked in the area shortly before the hour mark.
The visitors controlled most of the half, and Betis had to rely on its keeper to keep the score level as the match wore on. First, Adrian parried a bullet header from Aduriz, before Susaeta skipped into the area only to be denied by the 26-year-old goalkeeper.
Adrian saved his best until injury time, as Ibai Gomez's cross was turned goalwards by Oscar de Marcos, and Adrian showcased his agility to claw the ball away from goal and safeguard his side's share of the spoils.
The result leaves Betis in fourth place, while Bilbao climbs above Real Zaragoza into 13th in La Liga.