Juanma Lillo, a former coach in Spain's La Liga, is seen as a soccer swami for pioneering the 4-2-3-1 formation that has been used by six of the 16 teams at the Euro.
While Mr. Cruyff gets much of the credit for transforming Spain's approach, its recent success owes just as much to a little-known coach named Juanma Lillo, who devised the tactical framework that has underpinned La Roja's success.