India A 411 for 2 (Agarwal 220*, Shaw 136) lead South Africa A 246 (Second 94, Siraj 5-56) by 165 runs

The questions over India's top order remain unanswered even after the gripping Edgbaston Test. Shikhar Dhawan was one of the two batsmen that batting coach Sanjay Bangar, without naming, said had "thrown" their wickets away in the first Test. KL Rahul was the other one. And Cheteshwar Pujara's overseas form continues to be a mystery. Eighteen-year-old Prithvi Shaw and Mayank Agarwal, who were more successful in England for the India A team, applied further pressure on the senior side's top order and chief selector MSK Prasad, who was in attendance at the Chinnaswamy Stadium, by peeling off effortless centuries in a double-century opening stand against South Africa A on day two.

While Shaw was dismissed for 136 off 196 balls, Agarwal progressed to his second 200-plus score in the past year. He had hit an unbeaten 304 against Maharashtra in the Ranji Trophy last November.

More recently, Shaw had struck three hundreds in England, including one off 74 balls that headlined a remarkable comeback from India A against West Indies A at the Kent County Cricket Ground. Shaw marked his return to home comforts with an authoritative knock, studded with punchy drives in the arc between backward point and mid-off. That the sloppy South African attack kept feeding him width without generating much movement also helped Shaw. They bowled either too full or too short, before being battered into submission.

In the morning, fast bowler Mohammed Siraj needed just three balls to nip out the remaining two South African wickets and bowl the side out for their overnight 246, giving him a second five-wicket haul in first-class cricket. South Africa, in contrast, needed 353 balls to find their first breakthrough on day two.

It was Agarwal who had set the early pace: his first four scoring shots were all crisp fours. At the other end, Shaw was initially jittery, wafting and missing outside off, before tightening his footwork to regularly pierce the packed off-side infield. He raised the fifty partnership in the 11th over, when he nonchalantly flat-batted seamer Malusi Siboto through cover point. The next ball was punched through extra cover and mid-off with similar nonchalance. All told, Shaw took eight fours off Siboto in the morning session.

Spin was introduced in the form of Shaun von Berg in the 15th over, but the openers continued to drill down the deficit. Von Berg's third ball was a low full toss that was slog swept by Shaw for a one-bounce four. In the legspinner's next over, Agarwal ran down the track and carted a six over mid-off. Left-arm spinner Senuran Muthusamy wasn't spared either. At lunch, the deficit was down to 124.

Agarwal was the first to bring up a century after the break when he jabbed one to mid-off off his 102nd ball. He leapt twice and punched his fist before Shaw wrapped him up in a hug. Soon after, Shaw brought up a hundred of his own, off 116 balls, with a full-blooded slap to the right of slip. They ticked off the milestones and wiped out the deficit 20 minutes before tea.

The ball became softer, the field was spread out, and the bowlers were tiring. Shaw and Agarwal sat back and tipped the ball into the gaps, before offspinner Dane Piedt snuck an offbreak through the gate to bowl Shaw in the 59th over.

There was no stopping Agarwal, though. He moved to 150 off 172 balls with a violent loft over mid-off. His Karnataka team-mate and school-mate R Samarth then kept him good company in a 118-run stand for the second wicket. While every boundary from the local boys elicited cheers from a small Sunday crowd, the South Africans dug deep into their reserves.

They employed twin short midwickets and a leg gully against Agarwal and targetted the batsman's body with a volley of short balls. Even as Duanne Olivier hit the pitch harder, Agarwal rode the bounce and countered him. He reached a double-hundred when he firmly whipped Siboto to the midwicket boundary in the 76th over.

The second new ball then provided the visitors some respite as Olivier had Samarth reaching out for an outswinger with hard hands and edging behind for 37. Agarwal and captain Shreyas Iyer saw out the day and ratcheted the lead up to 165 at stumps.

While South Africa's senior team piled on the runs in an ODI in Kandy, the A team found itself at the wrong end of a seamless assault. All six bowlers used by them went at four or more runs an over.

Deivarayan Muthu is a sub-editor at ESPNcricinfo