And so it's that time again. Two clubs, two cities, face to face. Sunday night at Camp Nou: first versus second in La Liga. Two teams that are way out in front, two players too. First and second in the top scorer's chart, men who are breaking records at every turn; men who made history just seven days ago, splashed across the front pages on Monday morning. There they were on the cover of Marca, the country's best-selling newspaper, celebrating landmark goals above the headline: "Fury, unleashed."

No, not Barcelona and Real Madrid. Barcelona and Atlético Madrid. Not Leo Messi and Cristiano Ronaldo. Leo Messi and Radamel Falcao. This time last week, Deportivo la Coruña's manager, José Luis Oltra, said: "I think Falcao might just be the best striker in the world." He would say that: he had just witnessed the Colombian destroy his team. Atlético beat them 6-0 at the Vicente Calderón. Falcao scored five of them. Five. They were five goals that kept his team five points ahead of their city rivals, Real, and took Falcao into second in the top scorers' chart, three ahead of Cristiano Ronaldo.

Falcao had become the first player in La Liga to score five goals in a game in more than a decade and only the second Atlético player to do so. The last had been the Brazilian Vavá in 1958. It was the story of the weekend. Or, at least, it would have been had it not been for the fact that before Falcao and his team-mates had even departed, out through the car park under the north stand, Messi had scored twice 500km away against Real Betis, taking him to a record-breaking 86 goals in 2012. This game has been set up beautifully.

When Falcao left the Calderón, he was carrying the match ball in his hands. His team-mates had signed it. One had written: "For the best No9 in the world." A few hundred metres away, in the cramped press room, Atlético's manager, Diego Simeone, said much the same: "This is a historic night. Falcao is the best striker in the world." Pep Guardiola had expressed the same opinion six months earlier. Fabio Capello agreed.

When it comes to strikers, there are few like him. Probably none. Falcao, 26, calls himself a "specialist"; goals are an obsession, something he has worked on relentlessly. He recently told FourFourTwo that if you gave him a pen and a piece of paper, he could probably draw you a diagram of every goal he has ever scored. There would be many of them – he has scored 176 goals so far, finishing as the Europa League's top scorer two seasons in a row and with two different teams – and all different types, too.

This season he even scored his first free-kick. It was the first he had even taken. Typically, it emerged after the game that he considered free-kicks one of the flaws in his game and had been quietly practising them for months. What he has achieved is not chance. He has worked at it, perfected it. "He always wants more," says Simeone.

Last Sunday provided more proof. Five goals, all of them different: a chase through the gap and slotted finish. A drop of the shoulder from a throw-in and first-time shot on the bounce from the edge of the area, the ball flying into the net. A penalty, which he won himself. A diving header a yard out, boots flying by his face. And a cut back, shift inside, do-it-yourself goal to round it off.

Left foot, right foot, inside the area and outside, powerful and precise; he has an astonishing array of finishing skills. The efficiency is startling. Against Deportivo he scored five times. How many shots had he taken? Five. It was no one-off, either: Falcao has scored 16 in the league this season to Messi's 23 and Ronaldo's 13. He has taken 52 shots, less than half as many as Ronaldo, on 108, and significantly fewer than Messi on 79.

When he was a kid, a team-mate called Gonzalo Ludueña nicknamed him The Tiger. The name stuck. For an advertising campaign, Atlético recently put up signs round the Calderón: a red triangle warning of the tiger on the loose. The track that accompanied the footage was, inevitably, Eye of the Tiger. And for all that it is a cliche, there is something about it that feels right. There really is something predatory about the way he plays. Something about the way he moves that says stealth, ruthlessness.

One former coach describes him as spending much of the time on the pitch looking for "somewhere to hide", almost acting like he's not interested. He slips out of the defender's field of vision, always watching the move unfold, waiting for his opportunity. And when it arrives, he is there, fast. Before anyone can react, the ball is in the net.

"You have to be as complete as possible, you have to be able to do everything, or you won't score goals," Falcao says. "I never think I'm not going to score, I never panic, I never start to worry. I believe I will score. I just know, no matter how long I have to wait, that the goal will come."

Falcao reached 55 goals for Atlético in only 65 games. The question is how much longer he will be there; privately, the club admits that he will move on. His hat-trick against Chelsea in the European Super Cup in August brought him into focus in England and he is wanted in Spain, too. That old, familiar policy: if you can't beat them, buy them.

At a gala dinner this week, the Real president, Florentino Pérez, found himself on the same table as the striker. He joked with Iker Casillas that he had a napkin at the ready. It was a reference to how he signed Zinedine Zidane at a similar dinner in 2002, passing a napkin to him upon which he had written: "Do you want to play for Real Madrid?"

Whoever does sign him, it will cost them. Yet the evidence suggests it will be worth it. Falcao's buy-out clause stands at €60m. As ever, the figure was meant to be symbolic. Eighteen months later, it feels eminently sensible.