Despite Arthur's criticism of the Newlands surface, South Africa went to stumps on Day 2 of the second test on 382-6 in its first innings after a strong batting display. It is 205 runs ahead of Pakistan with four wickets in hand and in total control.
Du Plessis' ninth test century was completed soon after he built a 156-run partnership with Temba Bavuma, who made 75 but didn't quite see his skipper to three figures and finally ran out of chances after surviving two near-misses.
Both took a series of blows on the body in the course of their innings, testament to a challenging pitch that had cracks early in the game causing unpredictable bounces that caught batsmen off-guard on numerous occasions.
Du Plessis was hit twice on the fingers and once, late in his innings, on the helmet among other blows. Bavuma also took several, including a painful one in the ribs. The physios were out often. "I just think it's (the pitch) inconsistent," said Arthur, a South African and former Proteas coach. "I think there was seven stoppages for balls that hit cracks. And we're talking about Day 2. I understand if that's Day 4 or Day 5.
"It shouldn't make your first innings a lottery." Arthur's dissatisfaction stemmed from Pakistan's batting struggles on two tough pitches this series. The tourists were bowled out for 177 in the first innings at Newlands, the third time in three innings this series they've failed to reach 200.
That also underlined the challenge Pakistan faces to save the game and the series with South Africa's pack of four fast bowlers well-rested and ready to finish off the job. Pakistan needs its best total of the series to just make South Africa bat again.
"I'd say we've been outplayed here," Arthur said. "I don't think here we've played quite well enough to call it a game of missed chances." South Africa leads the three-match series 1-0 and another victory will confirm a seventh straight series win at home for the Proteas. They last lost on South African soil to England in 2015-16.
But there was something in the number of times du Plessis and Bavuma were hit to suggest that Arthur had a point about the pitch, and South Africa's desire to play and dominate on fast bowler-friendly pitches at home might recently have got out of hand. A test a year ago in Johannesburg against India was nearly called off for a dangerous pitch.
Arthur said the Newlands pitch wasn't dangerous but it and the Centurion surface for the first test were both sub-standard. Bavuma said it was difficult to bat on, nothing more. "It was challenging but not impossible," Bavuma said. "You've got to make peace that you're going to take a couple of blows on the body. I wouldn't call it dangerous. Faf is still living. I'm still living."
The stand between du Plessis and Bavuma was the best of the series. And even after Bavuma fell, du Plessis and Quinton de Kock put on another 51 to grind down Pakistan further. De Kock, who raced to 50 off 59 balls and was 55 not out at stumps, appeared ready to dish out more on Day 3.
Du Plessis arrived at the crease in the second over of the day and left around a half hour before the end. In between, he and Bavuma took the Proteas from a promising position to one of dominance. Bavuma survived two chances, the first coming early in his innings when an edge to Azhar Ali at first slip was adjudged by the TV umpire to have hit the ground just before the fielder scooped it up. He also successfully reviewed an lbw decision when on 65.
Bavuma missed out on a century when edging behind to Shaheen Afridi, but du Plessis didn't, hitting 13 fours and battling gamely through the tough periods. Du Plessis also fell caught behind to Afridi, who finished with 3-112, but Pakistan's bowlers didn't have the same success as South Africa's, who tore through the tourists on the first day, aided by the pitch.
The second day started well for Pakistan, too, when Mohammad Abbas bowled Hashim Amla with a delivery that jagged back dramatically off one of those cracks and knocked the leg stump out of the ground.
Pakistan also removed Theunis de Bruyn for 13 to have South Africa 149-4 before the du Plessis-Bavuma stand. Those two saw out the first session and batted through the entire second session, their partnership lasting nearly four hours and almost certainly taking the game and the series away.
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