The hosts started brightly and put the Betis defence under pressure right from the off. After just three minutes, Pau Lopez made a strong save to deny Braga captain Ricardo Horta from giving the hosts a very early lead.
However, there was nothing Lopez could do about Braga’s next effort just moments later, as a corner from Diego Rodrigues found Florian Grillitsch at the near post, and the Austria international finished superbly for his third goal of the season.
For a split second, Betis thought they had netted an instant equaliser when Marc Bartra found the back of the net from close range, but his strike was immediately ruled out for offside.
Bartra was left frustrated again shortly after the midway point of the first half, as he saw his powerful header hit the post before Lukas Hornicek was called upon to produce a great block and prevent Abde Ezzalzouli from levelling the game.
The Heliopolitanos continued to build momentum as the first half progressed, and only an outstanding save from Hornicek stopped Cucho Hernandez from equalising after 37 minutes.
Nevertheless, Manuel Pellegrini’s side eventually drew level a quarter of an hour into the second half. After Jean-Baptiste Gorby brought down Ezzalzouli inside the box, referee Felix Zwayer had no hesitation in awarding a penalty, and Hernandez emphatically converted the subsequent spot-kick.
The latter stages of the encounter were tense, with both sides aware that a second goal for either team could prove to be absolutely crucial.
Ultimately, though, despite the best efforts of each outfit, a late winner could not be found. It is therefore all to play for when the teams meet in Seville next week, with the winners of this tie facing either Freiburg or Celta Vigo in the last four.