South Africa enforcer Morne Morkel is ready to shoulder the extra burden resulting from left-armer Wayne Parnell’s groin injury.

The Proteas will be without home-town hero Parnell in Port Elizabeth when they attempt to skittle Australia on day four of the second Test.

Should Australia offer more resistance than in the first innings, when they lasted 57 overs in the face of some excellent bowling from Morkel, Vernon Philander and Dale Steyn, it could place extra strain on the pace trio.

It will be a delicate issue for captain Graeme Smith to handle, given the potential series decider starts on Saturday in Cape Town.

“It’s a big blow. Wayne knows these conditions very, very well and the way he started off was good. His first spell was fantastic,” Morkel said.

“He’s also a guy that can swing the ball. It’s going to put an extra workload on us in the second innings, but it’s one of those things and we need to deal with it.

“There’s a Test match there to be won and if we have to put that extra bit of effort in then the bowling unit will do that.”

Morkel struck Mitchell Johnson on the hand and helmet with consecutive boundaries on Saturday, and looked just as dangerous as the left-armer did in the first Test.

The 29-year-old suggested there was no sense of payback or comeuppance after Johnson inflicted so much pain in Centurion.

“There’s no competition about who’s going to bowl (more aggressively), whose ahead the captain will come up with a plan,” Morkel said.

“It’s not like a battle between ‘I’m going to bowl a bouncer and you’re going to bounce me’. It’s more strategy.”