Cape Town - The big squeeze is already on for places in the Proteas' all-important top three at Twenty20 international level.

While the first-up Test series against England undoubtedly represents the premier business of their looming tour here, the two white-ball formats (three ODIs and three T20 internationals) immediately afterwards will also be of extra interest with next year's ICC T20 World Cup in Australia in mind.

In that respect, the race has certainly begun for berths in the Proteas' plans - and especially in the top-order batting slots.

They are critical positions in the game's shortest international version, given how often the top three are the likeliest to be able to play suitably lengthy innings: it is very common for all batsmen from No 4 down in a line-up to effectively have to play roles as finishers rather than have any luxury of playing themselves in to a meaningful extent.

Getting selection right at one, two and three, then, is a vital element of a successful team brew: they are the players tasked with not only setting a strong platform but also ensuring a suitably rollicking tempo in the first-six-overs powerplay.

As things stand, and with the ongoing Mzansi Super League a clear illustration, South Africa have increasingly fierce competition for those berths.

Of the leading runs-scorers in the competition so far, five of the top six performers statistically (Englishman Liam Livingstone the odd man out, as he has more regularly batted at four for the Cape Town Blitz) can be branded specialists in top-three positions in the order.

The pile is headed by Janneman Malan, the crisp-striking right-hander with the Cape Town Blitz, pleasingly only 23 years old and the sort of relatively new face South African cricket badly needs.

Already blooded in two T20 internationals against Pakistan last season, in which he made a promising 33 on debut at the Wanderers, the Nelspruit-born customer has amassed 298 runs from eight MSL innings at an average of 42.57.

Renowned for his ability to play assertive, usually safely lofted drives over the infield, Malan is also striking at a rosy rate of 150 - the best of the top five run-scorers so far.

Boasting a top score of 99 not out in the opening round against the Jozi Stars in the Bullring, Malan has been a bastion of consistency and not yet fallen in single figures.

Running neck and neck against each other as they have done all campaign - and despite the Jozi Stars' broader, still-winless troubles - are Reeza Hendricks in second place (275 runs at 39.28) and captain Temba Bavuma in third (232 runs at 38.66, from one less knock).

Bavuma had an especially good mini-series (drawn 1-1) for the Proteas against India away at the start of the summer, too, with his whippet-like fielding an extra asset to the cause.

While 31-year-old Jon-Jon Smuts may have a more difficult task now to crack the SA T20 squad - he averages 15.75 after eight prior opportunities - the all-rounder from the Nelson Mandela Bay Giants is nevertheless the fourth-highest tournament scorer at the moment with 205 runs at 41.00 (strike rate 140) so he remains thereabouts in a Proteas context with his ability to chip in slow left-arm fare as well.

But the SA top-order race is spiced up further by the fact that two proven stalwarts at the highest level remain right in the frame: regular captain Faf du Plessis (though he sat out the Indian T20s) and wicketkeeper/opener Quinton de Kock.

Neither has set the MSL alight yet - there is still a bit of time for that - but their international T20 credentials are entirely beyond doubt.

Remember that Du Plessis has played all but seven of his 44 T20 knocks for the Proteas in the No 3 berth he so clearly relishes, and averages a touch under 39 there (strike rate 137).

The X-factor-laden De Kock, meanwhile, was a majestic SA figure in the decent series outcome in India, blasting 52 in Mohali and 79 not out in Bangalore, while his glove-work remains right up on the premier tier worldwide.

South Africa's one, two and three in T20s over the next few months? It's a pleasantly tough ask for the selectors.

Well, when we actually have a panel, of course ...