Test cricket should be tough for rookies. Even rookies who have cruised through seasons of domestic cricket, destroying all in their path. Even rookies who look as though they were born with an international shirt number embroidered on their soft baby skin. It should require fumbling, falling flat and making mistakes.

Dean Elgar was probably given to wondering why it was all so easy for Faf du Plessis. Du Plessis was South Africa's saviour on debut when he turned a potential Test defeat into a morale-boosting draw which led to a series win in Australia. Michael Clarke was officially named as man of the series, but Du Plessis' team-mates triumphantly hailed him as their own choice.

Crucially, du Plessis looked like he belonged. He had the temperament to make the step up. Under extreme pressure, du Plessis was able to defend tirelessly in Adelaide and attack cautiously in Perth. His start suggested that the changes he made to his game by moving up the order for his domestic franchise and turning down a T20 deal with Somerset to captain South Africa A in unofficial Tests had paid off.

If du Plessis could make the transition so easily, Elgar must have thought as he sat on the sidelines in Adelaide, then surely I do the same? Elgar's first-class record has been consistently better than du Plessis over the last three seasons and he has played more matches. Over the last three seasons Elgar averaged 50.11 in franchise cricket in 32 matches (not accounting for other matches for teams like South Africa A) while du Plessis played half that number and averaged 40.47.

They both played in the June matches against Sri Lanka A and both contributed heavily to South Africa's victory. Elgar top-scored with 171, du Plessis made 144. Given Elgar's form in first-class cricket, it was thought he would be picked for South Africa in the longer format first but instead he was chosen to play in the one-day series against Sri Lanka. Du Plessis was already in the set-up at limited-overs level.

Before any cricket began, Elgar sustained a serious knee injury that kept him out of cricket for the rest of the summer. Du Plessis went on to score an important 72 in South Africa's win in Bloemfontein and their paths went in opposite ways. Du Plessis was picked as a replacement in England, Elgar was part of the one-day set up where he fared modestly and both were taken to Australia knowing they would only be called into action if something happened to JP Duminy or Jacques Rudolph.

That something happened first for du Plessis when he took the place of the injured Duminy and he made everything of it. Something also happened when Rudolph's rope ran out and Elgar was inserted into his spot. The difference was that Elgar did not look comfortable at all.

His pair alone did not suggest that. Many rightly pointed out that Graham Gooch and Marvan Atapattu were among the batsmen to have gone run-less in their first Test and built impressive careers after that. Elgar could simply have got unlucky but he did not.

He was worked over by Mitchell Johnson on that Test debut in Perth. The left-armer started with bouncers in the first innings, hurrying Elgar into shots as he searched desperately for his first Test run. Then, Johnson began to pitch them up and just when everyone but Elgar was expecting a short ball, Johnson delivered one and he was caught off the glove, hooking.

It took Johnson even fewer balls to get the same result in the second innings when he followed up three bouncers with a length ball and Elgar padded up to it. For a batsman who had handled bounce around South Africa for years to have been so conclusively rattled by it was surprising. Welcome, international cricket said to Elgar, you've fallen into the gap.

Gary Kirsten's way is to give players sufficient chances and Elgar was informed he would keep his place for the less challenging task of facing the New Zealand attack. Even then, in the first Test in Cape Town, Elgar did not look like he fitted in.

Coming in after a century from Alviro Petersen and 60s from Jacques Kallis and Hashim Amla, Elgar had a stable platform from which to launch. He scored a run off his first ball but still did not look entirely sure of himself. His footwork was uncertain, his early drives nothing but tentative prods and he seemed to lack the confidence to play outside the off stump. He struggled to bring his bat down straight. Suddenly, despite a reputation for possessing one of the tightest techniques in South Africa, Elgar looked out of his depth.

The early parts of his innings in Port Elizabeth were similar. He was nervous, drove loosely, pulled uncertainly. After three attempts at the shot, he got it right and controlled the ball well to the mid-wicket boundary. That was the first sign that Elgar could step up.

As the innings progressed, Elgar straightened his bat and began to time the ball well, especially on the drive. He displayed some patience and much skill, living up to his classy domestic reputation. Bearing in mind that Elgar is usually an opening batsman, adjusting to the lower middle order was perhaps always going to take some extra time. By his own admission, he had to develop an understanding of how to handle batting with the bowlers.

But he had them to thank for being able to get to his first Test hundred. Despite wanting to declare at tea, Graeme Smith sent out the lower order to allow Elgar to bring up the milestone and it was not a gratuitous concession. Although cricket remains a team game, with the amount of time left in the game to leave Elgar nine short would have denied him the opportunity of a confidence booster.

Now, a Test hundred to his name, he feels as though he has done something to prove he has a Test career ahead of him. Du Plessis' phenomenal rise will always serve as a reminder that some people were just born to play Test cricket but it's the lesson Elgar teaches that is more notable. Most players do not learn to bat and bowl before they learn to crawl, walk, talk, scrape their knees and fail on the way to success. Elgar has walked that road now. And it is still only his third Test.