After a disappointing slip-up against Las Palmas extinguished any lingering title hopes, Diego Simeone's men responded with a show of strength, climbing to 66 points - six clear of fourth-placed Athletic Club - and sending a message to the rest of LaLiga.
"This one had everything - intensity, quality, and in the second half, real composure," Simeone said after the final whistle. "That third goal was pure class."
It didn't take long for Atleti to impose themselves. Just three minutes in, Alexander Sorloth rose to meet Giuliano Simeone's delivery at the back post, nodding home with authority. The Norwegian looked hungry for more, nearly adding another moments later, but was denied by a sharp stop from Augusto Batalla.
The Rojiblancos kept their foot on the gas, and Conor Gallagher - looking increasingly at home in red and white - doubled the lead before halftime with a clinical header off Rodrigo De Paul's teasing cross.
Rayo showed flashes of their attacking threat, but Atletico's defensive backbone held firm, with Jan Oblak turning away everything that came his way-most notably efforts from Isi Palazon and Alvaro García.
Julian Alvarez put the final nail in Rayo's coffin with a composed finish in the 77th minute, capping off a silky move orchestrated by none other than Antoine Griezmann. It was Alvarez's 27th goal of the season across all competitions - but he's not counting.
"I'm just focused on getting better," Alvarez said. "The league might be out of reach, but we're still pushing every day. It's about finishing strong."
Rayo, to their credit, showed fight and ambition, and despite the result, left with their heads high.
"We didn't quite have the finishing touch tonight," admitted Palazon. "But we had moments, and we showed courage. That's what we take with us."
The loss leaves Rayo mid-table in 11th, five points adrift of the European qualification places. For Atletico, meanwhile, the mission is clear: secure that top-four spot and build momentum toward the next chapter.