Webb was selected to officiate at the 2007 U-20 World Cup in Canada and his first appointment was a Group D match between Poland and Brazil at Montreal's Olympic Stadium. He then took charge of a group C game between Mexico and Portugal at the National Soccer Stadium in Toronto and a group A match between Canada and Congo at the Commonwealth Stadium in Edmonton. Webb was retained for the knock-out stage of the tournament, and refereed a quarter-final in Montreal where Chile defeated Nigeria 4–0 with all four goals being scored in extra time.