The Ashes has finally arrived with Steve Smith scoring one off the best hundreds of his career. However, the opening day was also famous for a new rule implemented by the International Cricket Council in concussion substitutes. The change seeks to protect players who suffer head blows, while also compensating teams with a like-for-like player to replace the injured cricketer. To discuss the growing international awareness for concussion and the reasons for this new cricket law, we were joined by Dr Alan Pearce from La Trobe University to discuss the events.