 Complete the following phrase:  Before the controversial Test series during Australias Tour of South Africa in 2018 commenced, Australian spinner Nathan Lyon commented on sledging: We know where the line is. We headbutt it, but we dont go over it. Following the 2018 Australian ball-tampering scandal, voices calling for a reformation of Australias cricket culture have emerged. Australian Prime Minister Malcolm Turnbull called for an end to sledging following the scandal. Following the outrage over the scandal, former Australian cricketer Justin Langer said that cricket would be dull without sledging. Australian batsman David Warner who received a one-year ban following the controversial series, exclaimed: I play with aggression on the field and I try not to cross that line. Former Australian cricketer and former coach of the Australian team Darren Lehmann has suggested that Australia is not as bad as portrayed, adding that sledging was worse during his own times. Australian wicketkeeper Tim Paine, in captaincy as replacement for Steve Smith who received a one-year ban from the 