- Rees-Zammit's versatility means he could battle either of Messrs Kolbe or Mapimpi directly ... but either way, it's one for connoisseurs.
- Both Kolbe and Rees-Zammit have high try strike rates at Test level: 13 between them from a combined 23 caps.
- The Welshman is the youngest Lions 2021 squad member, though not eclipsing Tony O'Reilly, a tender 19 against the Boks in 1955.
Whether they will mark each other directly in the series between the World Cup-holding Springboks and British and Irish Lions remains to be seen.
Just for one thing, callow 20-year-old Louis Rees-Zammit first needs to crack the Lions' Test team before any thoughts of a pulsating personal contest with the Boks' down-the-touchline talisman Cheslin Kolbe can be contemplated.
But at least the appetising prospect is a crucial step closer as Welsh wing flier Rees-Zammit officially made the extended squad nod - no major surprise - on Thursday, making him the youngest member of the 37-strong touring group.
His has been probably the hottest new name on northern-hemisphere rugby lips in recent months, and the Gloucester-based dynamo, who sports some Maltese blood, will take another herculean personal step forward on his burgeoning career chart if he makes the Test cut during the three-match international series against the host nation.
Rees-Zammit will not be the youngest Lions player if he does earn a Test cap during the trip: that honour still belongs to Irish wing Tony O'Reilly, as he featured in the first Test at Ellis Park - scoring a try in the visitors' thrilling 23-22 victory - in 1955 as a 19-year-old.
On the last Lions tour, to New Zealand in 2017 when the honours were shared 1-1 with one stalemate, English lock Maro Itoje (chosen again for this trip) was the youngest squad member, 22 at the time of selection.
For pure thrill possibilities, Rees-Zammit v Kolbe is arguably the most tantalising individual match-up you could possibly assemble in the 2021 series.
The Welshman has already shown admirable flexibility - and roughly equal attacking menace, really - between the left and right wings in his fledgling Test career to this point.
After debuting against France off the bench at Stade de France in October last year, Rees-Zammit started three Tests in a row on the left, before his next five (total tally nine caps at this stage) all came on the opposite side of the park.
Either way, he has already left defences constantly at sixes and sevens with his blistering pace, keen eye for a hole and - extraordinarily for such a raw figure - an almost veteran-like appreciation for opening up space to create opportunities for those around him.
He is already scoring tries (five) at a rate of just over one every other match in Welsh colours.
Interestingly, one of those challenging him for a wing berth in the coming series will be Scotland's South African-born powerhouse Duhan van der Merwe, a different type of beast with his greater emphasis on brute power than guile and deception.
But there must be a rosy chance, nevertheless, that Rees-Zammit and Kolbe will be entrusted with key game-breaking roles for their respective causes from 24 July, when the Test portion of the tour is scheduled to begin.
Kolbe continues to draw oohs and aahs in France for his tackle-evading, sublime-stepping exploits for Toulouse - as well as his famous tenacity on defence for a small-framed player - and should transfer that straight into the Boks v Lions series.
He is the right wing incumbent, and renowned for scoring one of the most inspired World Cup final tries with that electric thrust that bamboozled normally rugged tackler Owen Farrell, most notably, in the Yokohama showpiece against England in 2019.
The Kraaifontein-born "pocket rocket" - quite feasibly in the prime of his rugby life - has an even better try strike rate than Rees-Zammit, considering his eight dot-downs from 14 Tests.
One area where Kolbe would have an advantage over Rees-Zammit if they do go prominently head to head in the series, is in sheer rugby experience, even if there is surprisingly little difference between their Test cap tallies.
Although only first recognised for Test honours when Rassie Erasmus took coaching charge in 2018 - and hardly looking back - Kolbe, at 27, has a lot more "air miles" beneath his belt at first-class level, and Rees-Zammit has not yet played a Test either in the southern hemisphere or against a team from that side of the equator.
A direct-marking battle between the two would be something to savour hugely in the series.
But if Rees-Zammit were to have to mark 30-year-old current Bok left wing Makazole Mapimpi instead, that wouldn't be too shabby a prospect, either ... the last-named poacher extraordinaire has 14 tries from as many appearances.
*Follow our chief writer: @RobHouwing