A seed of tradition has been planted on the Philadelphia Union’s new soccer stadium, which will debut Sunday. The stadium's east side is designated as the "Supporters Section." That section will be populated largely by the maniacal Sons of Ben, who have already named their turf: The River End. "One of the things the Union seem to be trying to do is build tradition" — not easily accomplished with bricks and mortar, said Emily Sparvero, an assistant professor in the Sport Industry Research Center at Temple. "The way you do it is to leverage the historical or the geographical into the building of the stadium."