A lot of the early exchanges were played at a pedestrian pace, with Rayo often sitting back and doing whatever was required to limit their hosts. They also earned a half-chance when Alvaro Garcia was slipped through, although his unconvincing effort was deflected behind by Axel Witsel.
Atleti’s first notable opportunity came 20 minutes into proceedings, with Memphis sending an improvised attempt floating harmlessly over the crossbar.
That seemingly acted as a catalyst for Diego Simeone’s side to show greater attacking intent. Angel Correa was released behind Los Franjirrojos’ backline before seeing his effort saved by Stole Dimitrievski and was then denied by the offside flag.
The breakthrough eventually came when Reinildo Mandava rose between two Rayo defenders to meet Rodrigo Riquelme’s free-kick delivery and head home his first-ever goal for the club.
The hosts’ lead lasted just seven minutes, though, as Garcia collected Pep Chavarría’s pass on the edge of the box and drilled a pinpoint strike out of Jan Oblak’s reach.
Diego Simeone responded by bringing debutant Arthur Vermeeren off for Nahuel Molina at HT, and the substitute immediately showed a willingness to make runs behind.
That still didn’t do enough to satisfy the manager, who then made a triple change before the hour mark had been reached, and the Argentinian would have been concerned when García raced through shortly after.
The forward, however, sent an attempted chip floating into Oblak’s grateful grasp, and Antoine Griezmann couldn’t offer any greater test at the other end as his strike hit the side netting.
After having a goal ruled out, Memphis eventually latched onto a ball from Griezmann to convert his fifth goal in as many matches and send the Estadio Metropolitano into rapture, as Atleti earned their fifth consecutive win across all competitions.
Rayo, meanwhile, had Francisco Rodríguez sent off in the aftermath and have lost three of their last four competitive fixtures.
Flashscore Man of the Match: Pablo Barrios (Atlético de Madrid)