South Africa's champion at No. 3

A journey which began at Eden Gardens in Kolkata 12 years ago will reach a significant milestone in Johannesburg on Thursday when Hashim Amla walks out for the 100th Test match of his career, thus joining seven other South Africa players to achieve this feat. A 21-year-old Amla made his debut in that 2004 Test, and the early going was anything but smooth: he scored only 24 and 2 in his first Test, tallied 62 after his first six Test innings, and averaged a mere 25.50 after his first 15 Tests. The start was rough, but the peaks that followed have more than compensated for the poor beginning.

Over the last 12 years, Amla's batting has stood out for its sheer class and the ability to conquer all conditions and types of bowling. He averages almost 49 at home, 52 in Asia, 76 in England, and 46 in Australia and New Zealand. These numbers clearly demonstrate an ability to adapt to different conditions and bowling attacks. The runs have dried up in the last 18 months, and his career average - which stayed above 50 from his 65th to his 97th Test - has now slipped marginally below that mark, but hopefully, that is only a temporary blip.

During Amla's best five-and-a-half years, between February 2010 and June 2015, he averaged a mindboggling 66.43 from 41 Tests, with 16 hundreds in 69 innings. Among the 26 batsmen who scored 2500-plus runs during this period, his average was the highest, followed closely by his team-mate AB de Villiers, with Jacques Kallis also in the top six. In 15 series he played during this period (excluding one-off Tests), he averaged 50 or more in 11 of them.

With three batsmen in the global top six during this period, it is hardly surprising that South Africa dominated Test cricket and were clearly the best team of the time. They had a 23-7 win-loss record in those five-and-a-half years, while the next-best win-loss ratio was about half of South Africa's number: England were 30-18 in that period, a win-loss of 1.66 compared to South Africa's 3.28.

Amla's recent dip in form - he has averaged less than 34 in his last 17 Tests - has brought his career average below 50 after 99 Tests; if he gets out in both innings in Johannesburg, he needs to score at least 185 runs in the Test to ensure his average at the end of the game is on the right side of 50. Among the four other top South African batsmen who have played 100-plus Tests, three had higher averages going into their 100th - Kallis, de Villiers and Graeme Smith. Kallis and de Villiers averaged over 50 going into that landmark Test, but Amla's 25 hundreds is the highest among the lot. In fact, only six batsmen had scored more Test centuries after 99 matches - Sunil Gavaskar, Sachin Tendulkar, Matthew Hayden (30 each), Younis Khan (29), Ricky Ponting and Michael Clarke (26 each).

Of the 7665 runs scored by Amla in Tests, 86% have come at No. 3, which makes him the fourth-highest run-scorer at that position; only Kumar Sangakkara, Rahul Dravid and Ponting have scored more. Amla's average of 53.31 at that position is higher than his average at other positions, which is creditable given that he plays a lot of his cricket at home, where conditions are especially favourable for seam and swing early in the innings. Amla's home average at that position is 49.52, while away from home it goes up to 58.16 - that is a pretty clear indicator of the tougher conditions in South Africa for a top-three batsman.

Even more impressive than his overall average at No. 3, though, are his numbers at that position when South Africa lose an early wicket. In the 40 innings when he has come in with South Africa one down for 10 or fewer runs, Amla has averaged a phenomenal 61.22, with three 200-plus scores - including a triple-hundred - and a 176. His highest Test score of 311 not out at The Oval came after South Africa lost their first wicket at 1; his second-highest score of 253 not out in Nagpur started at 5 for 1. On both occasions, one opener had fallen for a duck. More recently against England in Cape Town last year, he made 201 after coming in at 7 for 1.

When the first wicket has fallen between 11 and 20, Amla has averaged 51.31 from 15 innings. Combining the two, his average when coming in to bat with 20 or fewer runs on the board is 58.59, which is the highest among the top four run-scorers at that position. The other three did very well too when they came in to bat early - Dravid's highest Test score came after the first wicket fell off the first ball of the innings, four of Sangakkara's 11 double-hundreds came after the first wicket fell below 10, while Ponting had 10 hundreds in 70 innings - but Amla's average in these situations is just a touch better than the others.

One of the key features of Amla's career has been ability to bat for long periods, regardless of whether he scores runs or not. In 168 Test innings, Amla has on eight occasions faced more than 300 deliveries. That includes his highest Test score of 311 not out, when he faced 529 balls and scored at a strike rate of almost 59, but also a 394-ball unbeaten 123 (strike rate of 31), when he defended relentlessly and almost saved the Kolkata Test against India in 2010. Then there was the unbeaten 139 off 382 balls (strike rate 36) against Sri Lanka in Colombo in 2014, which he followed up with a 159-ball 25 to help South Africa escape with a draw. (They finished on 159 for 8 in 111 overs, requiring 369 to win.)

Since the beginning of 1996, only four batsmen have faced 300-plus balls more than eight times in a Test innings. Sangakkara and Dravid have done it 16 times each, followed by Kallis (12) and Tendulkar (9). Amla shares the next slot with four others, which makes this a list of nine of the elite batsmen in Test cricket over the last 21 years.

The last couple of years haven't been as prolific, but that slump can easily turn around with a couple of big scores. Amla will turn 34 in March 2017, and will hope he has at least two more years of prolific run-making ahead of him.