Ashwell Prince has been dropped from the South African squad to play Sri Lanka in the third Test starting in Cape Town on Tuesday. Prince's absence makes it a certainty that recalled batsman Alviro Petersen will have a spot in the starting XI but it has yet to be decided whether Petersen will open or slot into Prince's role at No. 6.

Prince's place has been under scrutiny since the start of the season after he failed to score a half-century in either of South Africa's last two series, against Pakistan and India in 2010-11. He managed 109 runs in three Test matches this summer, including a half-century against Australia in Johannesburg in November, but failed to push on from there.

Prince paid the price for South Africa's spectacular implosion with the bat on the second day of the second Test against Sri Lanka in Durban, when they were bowled out for 168. Prince was dismissed for 11, the joint fifth-highest individual score on a dismal card, playing a reverse-sweep against Rangana Herath in the first innings. In the second knock, he was involved in a nightmare run-out, during which he turned his back on Hashim Amla, who called for a risky single, and it resulted in Amla's run-out. Prince was later dismissed for seven, a second failure in the match, after being moved up the order to No. 5.

Despite his barren patch, Prince has not been the only batsman under scrutiny of late. Jacques Rudolph, who made his comeback to the side after an absence of five years against Australia, was also thought to be fighting for his place. Rudolph forced his way back into national colours after two magnificent seasons at first-class level. He topped the 2010-11 rankings, with 954 runs for the Titans and managed 592 runs from four matches this season.

However, Rudolph has failed to translate that form onto the international stage. In seven innings, he has top-scored with 44. Although Rudolph has looked confident at the crease, he has often been dismissed playing reckless shots and admitted that he wanted to be "more selective" in his stroke-play. He has also confessed to feeling some pressure to perform at the highest level and that may have played a part in weighing him down.

His struggle for success in the opening berth makes it likely that Rudolph will be the one to move to in to Prince's spot at No. 6 while Petersen will return to the top of the order, where he has already had success. In nine Tests, Petersen averaged 33.64 but had to make way for the prolific Rudolph.

Since being dropped, Petersen has scored three first-class centuries, including one for South Africa A against a touring Australian side. Although he said it was "not nice getting dropped from the national team," he hinted that it served as motivation to keep performing.

"Every time I played for the Lions, I was focused on that game, that day and that session," Petersen said in Cape Town. "That really helped me a lot. I wasn't grumpy about being dropped." His place in the batting order has not yet been discussed but Petersen said he has no preference about where he would like to play. "I'd bat one to 11 just to be able to play for South Africa," he said.

Prince could do well to look at how Petersen reacted, since he will have to do the same to get his place back. With five rounds of SuperSport Series cricket coming up, Prince will have plenty of opportunity to prove himself ahead of tours to New Zealand and England next year.

A source told ESPNcricinfo that Prince took the news well and left the squad determined to do whatever it takes to book his flights to those destinations. "He has been through this before," the source said. "And he knows what he needs to do to get back in the side."

Prince was dropped previously in 2002 and spent three years out of the team before making a comeback in 2005. He was also missed out on a place when he injured his thumb in late 2008, just before the series against Australia. JP Duminy replaced Prince and performed so well that there was no longer space for Prince in the side. He was eventually tried in an opening role but when that failed, was moved back down the order.

Meanwhile, Vernon Philander has been declared fit for the third Test. Philander suffered a mild strain to his left knee while training in Durban and sat out during the Boxing Day encounter. His replacement, Marchant de Lange, took seven wickets in the first innings, making him the eighth debutant to take a five-for in 2011. Despite his sensational start to Test cricket, de Lange is expected to make way for Philander, after Morne Morkel showed signs of returning to form in the second Test.