Moeen Ali has insisted that England's bowlers will be key if they are to claim victory in the final Test with South Africa.

The tourists trailed by 175 runs with the Proteas at 42-1 by close of play on day three in Centurion following a first innings in which Kagiso Rabada starred, taking 7-112 to leave his side in pole position.

"We're disappointed at the moment but we know there are two important days coming up and we have to be ready," Ali, who contributed 61 from 101 balls, told Sky Sports News. "We are still going to be positive and try to get something out of this game.

"We're a side that have got bowlers who can win us a game, as we saw last week at the Wanderers. Hopefully we can do that again. We have to attack them when they come into bat and try bowl them out as quickly as we can.

"We've got two of the best bowlers I've ever played with. We saw at the Wanderers what Broady (Stuart Broad) can do and we obviously know what Jimmy [Anderson] can do."

Stephen Cook (23*) and Hashim Amla (16*) will resume at the crease on Monday morning.