Mitch Marsh posts strong half-century in Durban

Mitch Marsh's patience and Mitchell Starc's power has pushed Australia to 8-300 at lunch on day two of their first Test against South Africa.

Marsh resumed on 32, with his side 5-225 and the four-Test series opener very much in the balance on Friday morning.

The allrounder extended his mature innings, exercising great caution after the Proteas took the second new ball to be 60 not out from 147 balls at the meal break.

Starc adopted a more direct approach, especially against Keshav Maharaj, swinging freely and striking six boundaries in his knock of 35 that shifted momentum yet again in the topsy-turvy clash.

The session ended when left-arm spinner Maharaj bowled Starc, snagging his fourth wicket of the innings.

"If we can get up to 350 on this wicket that'd be a really good total," Marsh said prior to the start of play.

"It will turn more and more. Hopefully Nathan Lyon has a few overs in him and he can spin us to victory."

Marsh, maligned throughout the early stages of his Test career, is now averaging 126.66 with the bat since his Ashes recall.

The West Australian survived a testing examination from Kagiso Rabada, although he offered a sharp return catch on 42 that the speedster was unable to snatch in his follow through.

Rabada removed Tim Paine with the second new ball and threatened to quickly roll the visitors in a magnificent opening spell of express pace and rearing bounce that belied the slow pitch.

Paine was caught behind then the next delivery went within a whisker of kissing the top of off stump, with Pat Cummins boldly shouldering arms.

Cummins, promoted above Starc after a productive Ashes with the bat, spent almost an hour at the crease but managed only three runs before a straight ball from Maharaj clean bowled him.

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