The coin has flipped. South Africa have won their first Test series under Mark Boucher, their first in three against Sri Lanka and their first since January 2019.

While there are caveats that come with this victory - most notably that Sri Lanka were denied seven first-choice players by injury across the two Tests, including several who played roles in their 2-0 win here two years ago - the confidence that South Africa gained from turning their fortunes around can't be devalued. Winning, they say, is a habit and one South Africa had been out of for most of the last two years.

It is still going to take a lot of work before South Africa can look at themselves as a complete package, and sterner challenges await in Pakistan and against Australia, but this series has laid the foundations for rebuilding.

Here are the big positives for South Africa, and a couple of things for them to think about as they navigate five more Tests this summer.

No KG, no problem

What could have been South Africa's biggest disadvantage turned into an opportunity, after Kagiso Rabada did not recover from a groin injury in time for the series. South Africa's attack had just 12 Test caps between them going into the Boxing Day Test and, at first, their inexperience showed.

They struggled to adjust their lines and lengths after it became apparent that they were over-relying on the short ball and Sri Lanka racked up their highest total in South Africa, by some distance. But the home attack recovered well. Wiaan Mulder, playing in his second Test, led the comeback through nothing more complicated than discipline and debutant Lutho Sipamla cleaned up the tail. The pair, both just 22, continued to impress as the series went on and point to a talent pool that is not as shallow as was feared.

In Mulder, South Africa have a genuine allrounder who understands his role as a holding bowler but has the skill of using subtle movement to take wickets. In Sipamla, they have a genuine strike bowler, who can find speeds close to 140kph, and is meticulously accurate.

Sipamla, in particular, has made a case to challenge for the third frontline seamer spot. He had a tough start when he conceded 66 runs in his first 12 overs of Test cricket but returned to take 10 for 101 in his next 27.5 overs. He provided strong support for Anrich Nortje, South Africa's fastest and fiercest bowler, and Lungi Ngidi, who has lost a yard of pace but gained in maturity. Ngidi's variation through adjusting his seam position is an illustration of the work he has been doing with bowling coach Charl Langeveldt and adds a string to his bow.

South Africa will still welcome Rabada back with open arms when he is match fit but this series showed they have options and are developing healthy competition for places.

Faf's far from finished

The former captain is not about to become a former player anytime soon and world cricket can look forward to more free-flowing play from Faf du Plessis. Even though he didn't rate his 199 at SuperSport Park among his best innings, he acknowledged that it made a statement about his intent to stick around.

du Plessis is an important cog in the South Africa line-up and will act as the bridge between the previous generation and the future one. His experience means he can absorb pressure and assist the new captain along with shouldering the responsibility of run-scoring in a line-up that still needs to click.

What to do about the middle-order?

The reason the batting is still under construction is because the middle-order remains unsettled. Rassie van der Dussen starred in a match-winning partnership with Dean Elgar in Johannesburg but has gone 43 international innings without a hundred and would probably agree that his 67 at the Wanderers was not his most convincing. de Kock has been promoted to No.5, despite his excellent record at No.7, which leaves Temba Bavuma to bat with the lower order - arguably a waste of what he can offer.

It is now five years to the day since Bavuma scored his only Test century and although he makes telling contributions, there is pressure on him to convert, not least because of the ways he was dismissed in this series. He walked in Centurion, to a ball he did not hit, and shouldered arms to an inducker at the Wanderers.

South Africa have managed to lengthen their line-up by including an allrounder at No. 7 but need consistency out of Nos. 3, 5 and 6 to be able to show their full potential.

Test captaincy candidates

de Kock scored just 28 runs in this series and did a tidy job behind the stumps and though he has indicated he would continue in the role if asked, he does not appear to be a natural fit. On the field, a committee including du Plessis, van der Dussen, Elgar and Bavuma are involved in decision-making and South Africa may choose between the latter three when making a permanent appointment.

Elgar's form in this series, which he finished as the top run-scorer, has potentially put him at the front of the queue though the selectors are probably still wondering if Bavuma or Aiden Markram could be long-term options. Bavuma will need to solidify his spot before he can be seriously considered while if Markram has a decent summer, it may be difficult to look past him. For now, the search continues.

Firdose Moonda is ESPNcricinfo's South Africa correspondent