S1·E57 The Man Who Knows 21

When Monta and Sena are sent to spy on the Poseidons' final practice before the game, they are caught, and Kakei tells Sena that he wants to challenge Eyeshield 21 from the Devil Bats and prove to him that he will never match up to the "real" Eyeshield 21. Sena gets past him using the Devil Bat Ghost, but Hiruma, who had been watching, tells Sena that it was not Kakei's true strength he was running against.