The Frenchman is now the team's top scorer and his double against Rayo took his tally to 10 goals this season in La Liga, via Whoscored.com.
It's a fantastic achievement in Griezmann's first campaign with last year's title winners and even more so given his slow start to life in the capital.
"We’ve been saying it since November. He’s grown as a player and he’s just what we need," admitted manager Diego Simeone to the press, via AS.
On top of the goals he scores I also really like how hard he works. He can play out on the wing but also anywhere along the forward line. His pace and talent make him really disruptive.
That hard work was evident vs. Rayo, as Griezmann recovered the ball a greater amount than any other player on the pitch and was a constant threat, via FourFourTwo Stats Zone.
At Real Sociedad, Griezmann was primarily a winger, although he did feature, on occasion, as a striker when Imanol Agirretxe or Carlos Vela were unavailable.
Since making the move to the Vicente Calderon, his adaptability has continued, but he has played more as a supporting striker to either Mario Mandzukic or returning hero Fernando Torres.
Both partnerships are in their early stages, though there are clear signs that they can be very productive in the near future.
Griezmann has scored eight goals in seven appearances in a forward role, via Whoscored.com.
His mobility, pace, directness and dribbling technique mean that opposing defenders struggle to deal with him when he runs at them with the ball.
Griezmann is currently the same age that Torres was when he left for Liverpool. However, his level is quickly approaching that of his team-mate's previous time at the club.
Atletico's situation was obviously very different and therefore any comparison has to be adjusted accordingly.
Torres not only came through the ranks at Los Rojiblancos, but he had to carry the expectation of the club in very difficult circumstances.
Griezmann joined the reigning Spanish champions last summer, and although they have much better players nowadays, the expectancy for Simeone's men is naturally higher.
He won't feel an individual responsibility like Torres had at his hometown club, but if he persists in the same vein, then that will alter.
The stylistic similarity between the French 23-year-old and the Torres of 2007 is pretty obvious, even though Griezmann has only recently been converted to the position on a more regular basis.
Griezmann's pressing enabled him to breakaway for the opening goal against Rayo, whilst he latched on to a through ball for his second, with the two strikes reminiscent of Torres at his very best.
"We're really pleased for Griezmann and his two goals," said midfielder Tiago after the match, per Marca.
He seems to put every chance away. He's very quick and very skilled. You have to make the most of players' form. Right now, Griezmann is giving us goals and good football. He's had to adapt to a ready-made team. He's done that well and you can see he's enjoying himself out on the pitch. He's adapted to our defensive game, which he struggled with early on. He's going to be a very important player for us.
As I noted here, Torres will have to adjust his game in his second spell in Madrid, but the onus to reproduce his former glories will become less if Griezmann maintains his present form.