Cape Town - What we got at the Bullring on Sunday was a reminder of why the Proteas simply cannot be written off as contenders for the CWC 2019 honours, despite the swelling crop of other candidates for it.

That reminder came in the shape of imperious displays from several of their more established, proven stars - the spine of the team, if you like - as Sri Lanka were near-ruthlessly dismantled by eight wickets in the first of five one-day internationals.

Autumn evening shadows hadn’t even descended on the sun-soaked ground in a comprehensive way when the job was completed with more than 11 overs to spare.

It was almost all good stuff on the day, as the national team - with captain Faf du Plessis immaculately to the fore as a stroke-player - powerfully began the task of settling a bilateral score with the shock Test-series winners.

There’s a “but”, though.

Ungenerous as it may sound, this performance was engineered by steely seniors in the home ranks: players guaranteed their passages to the UK-staged World Cup from late May.

So at least for a few days onward in this series, we’ve all been left none the wiser about certain vexing holes in the 15-strong squad that will need to be assembled for the major global event.

And yes, there are now only four further games left for any “trial” purposes, beginning with the second ODI just up the highway at SuperSport Park on Wednesday.

In a nutshell, Sunday proved extremely prosperous indeed for the 34-year-old, 130-cap Du Plessis (112 not out), 26-year-old, 102-cap Quinton de Kock (81) and no less importantly the evergreen attacking spinner Imran Tahir, holder of 95 caps and a huge factor in the “middle” period of an opposition innings once again with his haul of three for 26 in a full quota of overs on Sunday.

Two other certainties, you would think, for the CWC party, opening bowlers Kagiso Rabada and Lungi Ngidi, looked sprightly in their own ways: the former ran in with gusto and kept sending down thunderbolts close to the 145km/h mark, while the latter only enhanced his growing reputation for prising open top-orders early.

Du Plessis made batting look near-effortless on this occasion, cantering to his 11^th century with poise and elegance yet without having to resort to any pronounced pyrotechnics or high-risk cricket to maintain a rosy strike rate - always the hallmark of a high-calibre and street-smart player.

Interestingly, too, he reassumed the No 3 berth: this was just his second time doing that in his last 12 innings in the format, and it is also where most of his career success has come.

As many as 10 of his tons have been carved out at “first drop” and he averages nearly 55 in the spot.

A little inconveniently, though, the major partnership between Du Plessis and De Kock - 136 in some 21 overs for the second wicket - also meant that others in the Proteas’ line-up vying for World Cup tickets either didn’t get to take guard or were subjected to strictly limited pressure; that was the case for Rassie van der Dussen, although his assured enough, unbeaten 32 did his cause no harm.

Two all-rounders wishing to fit through the funnel in that particular capacity at the tournament, Wiaan Mulder and Dwaine Pretorius, didn’t even need to reach for the pads, and their bowling contributions were moderate and inconclusive.

The pair went for 64 runs in a combined 11 overs, without getting a scalp, so the fierce debate around the various, versatile customers in the World Cup running simply continues without any sign of clear resolution yet.

Highveld limited-overs belters, seldom offering much in the way of “sideways”, aren’t always the best measure of medium-fast seam bowlers, either: perhaps only when the series gets to the coast (third ODI, Sunday in Durban) will there be a better examination of the suitability of Mulder, Pretorius and others to more English-type conditions ...

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