South Africa has racked up 615 runs thanks to Ryan Rickelton’s career-best 259 then reduced Pakistan to 64-3 by stumps on day two of the second test at Newlands.

Ryan Rickelton smashed his maiden double hundred and Kyle Verreynne made an aggressive half-century as World Test Championship finalist South Africa cruised to 429-5 on Day 2 of the second and final test against Pakistan on Saturday.

Ryan Rickelton moves joint-seventh in South Africa's all-time top scorers in a single Test innings after scoring 259 in the second Test against Pakistan.

Ryan Rickelton posted the joint seventh-highest score by a South African in tests with 259 as his side ran up a huge 615 before reducing Pakistan to an effective 64 for four at the close on day two of the second and final test at Newlands on Saturday.

Rickelton became the first Proteas opener to record a 250-plus Test score at home and the second overall after Graeme Smith, who recorded two double centuries in England in 2003.

Babar Azam remained unbeaten on 31 and was set to resume with Mohammad Rizwan, who was on nine, as Pakistan attempted to recover from their precarious position.

Ryan Rickelton moves joint-seventh in South Africa's all-time top scorers in a Test innings after hitting 259 in the second Test against Pakistan.

Makeshift opener Ryan Rickelton posted the joint seventh highest score by a South African in test cricket with 259 to help his side to a massive 566 for seven at tea on day two of the second and final test against Pakistan at Newlands on Saturday.

Pakistan 64 for 3 (Babar 31*, Ghulam 12, Rabada 2-9) trail South Africa 615 (Rickelton 259, Verreynne 100, Jansen 62, Abbas 3-94) by 551 runs Pakistan's horror day in Cape Town was complete after South Africa ripped through their top order to leave them staring down the barrel of a huge defeat.

South African wicketkeeper Kyle Verreynne said his side "need nine more big wickets" after the Proteas dominated Pakistan on the second day of the second Test against Pakistan at Newlands on Saturday.