Australia fast bowler Mitchell Johnson has insisted that his side must win the fourth Test this week if they are going to retain The Ashes.
The tourists are currently 2-1 down after a heavy defeat at Edgbaston, but the left-arm fast bowler has warned England that they are ready to play their best cricket.
He said at a press conference: "It's like a grand final for us. We really need to win this game. We have just got to focus on what we have been doing when we have been playing well. We have been training really well, that has been a real positive for us.
"When we are bubbly like that then normally we come out and play our best cricket. We have to take it one day at a time, one innings at a time and try and build those partnerships like we did at Lord's."
The fourth Test at Trent Bridge starts on Thursday.
