Marouelli's NHL career started on November 2, 1984, and wore a helmet while refereeing NHL games starting from the 1996–97 NHL season.[1]
On November 29, 2008, he officiated his 1,500th game between the Toronto Maple Leafs and Philadelphia Flyers.[2] On April 10, 2010, he officiated his last NHL game, between the Toronto Maple Leafs and Montreal Canadiens. At the conclusion of the game, both teams showed their appreciation for his long career by shaking his hand. In total, he officiated 1,622 regular season games and 187 playoff games.[1]