The incoming Bayern Munich coach has spoken about the positional switch that has now become synonymous with the Argentina international
The Spaniard, who will take over from Jupp Heynckes as Bayern Munich coach at the end of the season, transformed the Argentine from a wide player to a roaming attacking force during his four years at Camp Nou.
And the 42-year-old revealed what prompted him to recognise the potential in his talisman, while crediting former assistant and current Blaugrana trainer Tito Vilanova with foreseeing the striker's greatness.
"His movement in the middle of the pitch was second to none," Guardiola told reporters at a function in Buenos Aires.
"The position allowed him to come back looking for the ball without being followed by the defenders. That way, we were able to dominate in that part of the pitch and he had more freedom to come and get the ball.
"He seemed shy when I first met him, as always. He was with his father and I didn't know him, but Tito had told me he was going to be a sensation - and he was spot on."
The forward has continued to blossom in the wake of his ex-mentor's departure, inspiring his outfit to the verge of a 22nd Liga title.