Cape Town - The notable absence of "easy beats" from the remaining rosters of either team means that one of the Sharks or Lions could be virtually bidding farewell to any playoffs chances in Super Rugby 2019 when they clash at Kings Park on Saturday (17:15).
For the losing outfit - assuming we don't see the recently in-vogue outcome of a draw - the road will suddenly look immensely more challenging to qualify for the finals series.
That is because the long-standing, competition-wide mid-table fog is finally beginning to clear, and the process should only gather momentum this weekend.
After it, the vast majority of teams will have only three games left, and in isolated cases just two.
So the defeated side in the Durban derby (the Lions lie sixth overall, the Sharks breathing right down their necks in seventh, followed by a raft of other desperate teams) runs the risk of effectively slipping one win or more behind other candidates - from across the conferences - vying to make the cut, and ominously little time left to catch up surrendered ground.
It's a relative toss-up, after final whistle in the all-SA encounter, to decide which of the pair has the less enviable run-in: the Sharks must still negotiate one home games against the Hurricanes, and away meetings with the Jaguares before rounding off against old coastal adversaries the Stormers at Newlands.
Meanwhile, Swys de Bruin's charges would still sport two home dates - so a bit of an advantage? - against the Stormers and Hurricanes, but finishing at Loftus against the currently conference-leading Bulls.
It probably makes it a touch more essential that the Sharks come out victorious on Saturday, bearing in mind the looming pitfall of another long-haul passage for them to Buenos Aires, although defeat will certainly be a notably "eina" experience for either.
There is no shortage of reasons for Saturday's derby holding special appeal - hopefully a factor that will draw something resembling a proper crowd to the ageing stadium.
Perhaps the most obvious one is the Lions' obvious thirst for revenge after they were truly destroyed (42-5) on home turf by the Sharks on a damp Friday night in Johannesburg several weeks ago.
They will probably gee themselves up for the Durban return - this time anticipated to be in fine, benign weather - by believing that that champagne, "total rugby" showing from their opponents was a bit of a flash in the pan as the Sharks' habit has more customarily been to play an uncompromising, conservative, coal-face brand of the game.
But the formula has also earned them a handful of other decent results this season, including the memorable away draw with the Crusaders (only deprived of victory right at the death) and also triumph over the Waratahs in Sydney with a bit to spare.
We should see another intriguing clash of styles in this one: the Lions are almost certainly still the closest in this country to emulating a high-octane, "New Zealand" style of play and it has generally stood them in good stead for several years, considering their commendable appearance in three successive finals.
That said, they also seem to be well less of a title-hunting force this year, the philosophy bringing with it an undesirable error-rate and naivety at times among a thinner, more rookie-laden 2019 squad: it is reflected in the Lions' frankly unimpressive try ratio thus far: 41 for, and as many as 46 against despite their deceptively decent, present spot on the overall ladder.
Only the Chiefs and Sunwolves, the two worst-faring sides in the competition at this juncture, have leaked more tries than the Highvelders, so the Sharks may well fancy having another field day against these foes in that department: certainly a bonus-point win would do them the power of good, as well as largely put to rest their weird home bogey this year.
Robert du Preez's outfit, however, don't usually cross the "wash" prolifically: their 32 tries is better only, tournament wide, than compatriots the Stormers (a nadir of 23) and Bulls (28).
But they are extremely good at repelling the enemy from their own try-line, by stark contrast to the Lions ... just 29 conceded at an average of 2.41 per game, leaving them second only to the defending champion Cantabrians for defensive adhesiveness.
Different strokes from the two quite different "folks" in Saturday's encounter?
I wouldn't anticipate any dramatic formulaic changes, in either case ...
*Follow our chief writer on Twitter: @RobHouwing