Isaac Beacroft claimed a record-breaking victory in the 5km walk at the world U20 championships. (Joel Carrett/AAP PHOTOS)Isaac Beacroft claimed a record-breaking victory in the 5km walk at the world U20 championships. (Joel Carrett/AAP PHOTOS) Credit: AAPAustralia's Isaac Beacroft has maintained his stunning golden streak with a record-breaking victory in the 5km race walk at the world athletics under-20 championships in the US. Victory in Oregon means he now has the prestigious world U20 championships and Commonwealth Games gold-medal double. Despite the impressive nature of his victory, Beacroft said it was difficult to come straight from Glasgow to Oregon.