Split squads games are commonplace NHL preseason action, but doing them twice in the same building in rare. The Toronto Maple Leafs are preparing for a day-night doubleheader against the Ottawa Senators at Scotiabank Arena. While split-squad games happen all the time during the NHL preseason, a day-night doubleheader is extremely rare. Toronto has just 15 days of on-ice preparation before having to cut down their roster a day before their regular season begins on Oct. 12. The NHL also mandates teams to play a minimum of six pre-season games. The exhibition contests are coordinated with other teams and Maple…