|Occupation||U.S. Army Sergant|
|First appearance||9th December 1970|
|Last appearance||23rd December 1970|
|Number of appearances||2|
|Played by||David Cargill|
Sergeant Mario Ucello was a U.S. Army Sergeant and an old friend of Greg Flint and Gary Strauss. Stationed at Burtonwood he was the secretary to Major Ryan and rang Greg and Gary to summon to the base on the instructions of Ryan who was trying to trace AWOL Joe Donelli. A few weeks later, along with colleague Rod Malone, Ucello joined their two colleague at a party they held in the Rovers to say goodbye to their old friends from Weatherfield as they left the area to return to Germany. They formed an impromptu darts team and, despite their insistance that they had never played the game before, beat Stan Ogden and the regulars.