Sam Burgess is aware of the mammoth task that faces England when they meet Australia in a do-or-die clash on Saturday.
England's narrow loss against Wales last Saturday has made the fixture against the Wallabies a must-win for the hosts if they want to advance to the quarter-finals.
The centre, who spent four years in Australia playing rugby league, believes coach Michael Cheika knows what to say to get the best out of his charges and is expecting a titanic battle from a fired up side at Twickenham.
"Australia are very competitive, that's in their nature, plus they're playing England," quipped the 26-year-old.
"They will definitely come out of the blocks hard and fast. I know Michael Cheika and I know him pretty well, he will be getting the guys fired up.
"I expect another great Test and challenge and it's something to look forward to. There will not be many bigger occasions than this weekend.
"From us Australia can expect heart. If there's a time to put your body and heart on the line it's this weekend. A winning attitude is what we need on Saturday for 80 minutes."
Meanwhile, Burgess also heaped praise on fellow rugby league convert Isreal Folau, whom England will have to pay special attention to on the weekend.
"I've been watching a bit of footage on him and he's an unbelievable athlete," said the Bath player.
"He can move off both feet, he's strong, he's able to break tackles, stand in tackles and make things happen, so he will certainly be a threat.
"He's an all-round athlete and to play in three codes at professional level is quite unbelievable. He's looking very comfortable in union and he's enjoying his time. It will be tough to stop him on Saturday, but that's the job we have to do."