According to the rulebook, soccer is played on a grass field. Yesterday, though, the field surface became superfluous as Napoli strung together an immaculate, gravity-defying goal where the ball quite simply refused to touch the ground.In yesterday's Europa League match between Napoli and Danish side Midtjylland, defender Kalidou Koulibaly sent in a longball from the back to José Callejón, who did a near-slide-tackling touch on the ball to keep it aloft. The only time it touched the ground in roughly 65 yards was in the goal space. Pitch perfect.