 De Agostini was a tactically versatile and hard-working defender, who could play on the left, or even in the centre of his team's defensive line, although he was capable of playing anywhere along the left side of the pitch, due to his ability to cover the flank effectively and assist his team both offensively and defensively.He started out as a forward, but he was primarily deployed in the role of an attacking left-back or wing-back throughout his career, due to his pace, stamina, marking, crossing, positional sense, technical ability, and his capacity to read the game.He was also capable of playing anywhere in midfield, and was frequently used on the left wing, as well as in the centre on occasion, either in a box-to-box role as a "mezzala", or even as a defensive midfielder, due to his anticipation and tenacious style of play.