Following the departure of former coach Robbie Deans from the Crusaders, Blackadder was named as the sides new head coach ahead of the 2009 Super 14 Rugby Season. Blackadder led to the Crusaders to the semi-finals in his first year in charge losing to eventual champions the Bulls in Pretoria despite winning only one out of there first five matches at the start of the season. In his second year in charge, the Crusaders again fell to the Bulls in South Africa, this time 39–24. The 2011 season was a tough one for the side following the devastating Christchurch earthquakes which aside from causing loss of life and severely damaging the city, the earthquakes also wrecked their home ground at Jade Stadium. Amazingly the Crusaders managed to make the final that year after taking games throughout the wider Crusaders catchment area, New Zealand and even to Twickenham, however, the side fell tantalisingly close to a deserved victory as the Reds won their first title 18–13. In 2012 the Crusaders were knocked out by eventually champions the Chiefs 20–17 in the semi-finals before the Chiefs, on route to their second title, beat the Crusaders again in the semi-finals by the tighter margin of 20–19. In 2014, the Crusaders returned to the final but again fell short 33–32 against the Waratahs due to a last minute controversial penalty goal struck by Bernard Foley. In 2015 the Crusaders failed to make the finals, the first time Blackadder had not made them although the Crusaders extended his contract for another year. In late 2015 it was announced that the 2016 Super Rugby Season would be Blackadder's last coaching the Crusaders after eight years at the helm. In his final year the Crusaders were knocked out by beaten finalists the Lions 42–25 in Johannesburg.