The rangy Warringah flanker has been part of the North Harbour Rays NRC program since the NRC kicked off in 2014, after ticking many of the development pathway boxes along the way. After representing the Australian Schoolboys in 2010, and the Waratahs ‘A’ side in 2011, Killingworth was also part of the National Academy from 2011 to 2013.
A very handy Sevens player for both Warringah and NSW, Killingworth linked up with the Australian Sevens program after the 2015 NRC, and made his Sevens World Series debut at in Cape Town, during the 2015/2016 campaign.