Both sides’ respective cup exploits had taken precedence over their league campaigns this season, as the UEFA Conference League semi-finalists hosted the newly-crowned Copa del Rey winners.
That latest piece of silverware for La Real had already secured Europa League football for next season, but Pellegrino Matarazzo’s side certainly weren’t lacking motivation after a bright start here.
Ander Barrenetxea engineered a chance for himself in the opening exchanges, when he weaved his way into the Rayo box before his shot was parried to safety by Dani Cardenas.
Further opportunities then came for Duje Caleta-Car and Takefuso Kubo in a lively opening 15 minutes.
The visitors eventually drew first blood thanks to a moment of star quality from Mikel Oyarzabal, as he latched onto Barrenetxea’s pass and glided his way past several Vallecano defenders, before clinically dispatching his effort into the bottom corner.
The hosts looked to have responded immediately when Carlos Martin converted home from close range, but Andrei Ratiu was penalised for handball in the build-up, sparing the visitors’ blushes.
They did eventually find a wonderfully worked equaliser, though, when Sergio Camello showed some brilliant close control to navigate a tricky path through the Sociedad defence and fire a left-footed finish past Alex Remiro.
Camello spurned a golden opportunity to put Rayo in front shortly after the restart, but La Real were looking the more likely to add their advantage as the half wore on.
Cardenas was twice called into action to deny Oyarzabal and Orri Oskarsson, before the latter added his name on the scoresheet to re-establish La Real’s lead.
Sergio Gomez teed up the Iceland international, who took touches inside the box before calmly finishing past Cardenas at the end of a very well-worked Sociedad break.
Rayo looked to have wiped out Sociedad’s advantage again, when Pedro Diaz applied the deftest of finishes past Remiro, but the goal was controversially disallowed after a lengthy VAR review, determining that Ratiu had fouled Pablo Marin before the Rayo breakaway.
Oyarzabal made no mistake from the subsequent penalty, rifling the ball into the roof of the net amid the backdrop of the enraged Los Franjirrojos crowd.
It looked like a grandstand finish may ensue when Florian Lejeune converted from close range to halve the deficit, before Alemao headed home from close range deep into added time to give the hosts a share of the spoils.
It is a result which extends Sociedad’s winless run in LaLiga meetings to six matches. Additionally, La Real have now only won one of their previous five top-flight matches. Meanwhile, Inigo Perez’s side will be somewhat vindicated after that late moment of elation, increasing the gap between themselves and the bottom three to five points.