 She moved to Melbourne ahead of the 2013 season at the age of 20 and began playing for the Darebin Falcons in the Victorian Women's Football League (VWFL).She would play in her first VWFL premiership that season as Darebin defeated Diamond Creek by 49 points in the grand final.Brennan was drafted twenty-second overall by the Western Bulldogs in the 2013 women's draft and played for the club's representative side in exhibition matches through to 2016.