Dead rubbers in cricket are no fun. Players will insist that they take them seriously, but mostly it just allows a little bit of time to experiment. South Africa haven't got much more to experiment with. Instead, they'll probably be hoping to at least see their bowlers hit some form.
That, along with finding some stability in the middle order, is probably the only positive the Proteas can still salvage from this tour. We've picked four key battles for the fifth and final ODI.
Add your key battles for Sri Lanka vs South Africa in the comments.
South Africa's Bowlers vs. Themselves
The South African bowlers have, for the most part of their tour, been woeful. Their inconsistency has been galling, having conceded over 50 wides already. That's more than eight extra overs in total. It's simply not good enough. Not to mention Robin Peterson's dubious record of being smacked for 35 runs in one over.
It might not be much, but a solid bowling performance in the final game will at least inspire some kind of confidence in the visitors.
The Opening Pair vs. Time at the Crease
South Africa's batsmen have been equally average. The openers have struggled and the pairs have been mixed up too much. Sometimes because of injury, other times because South Africa are desperate to find something that works.
Even if they don't win, getting the opening pair to spend some time at the crease, as a pair, will be pivotal.
Cricket vs. The Weather
The weather in Colombo is not looking good. While the forecast for an island can hardly be trusted, a thunderstorm is likely according to Weather.com. Weather interfering with cricket is part of the game, of course, but it would be a great pity if the final game is rained off. Duckworth-Lewis might come into play, but even that won't do Sri Lanka any justice. Their players have been brilliant, and they deserve another chance to stamp their authority to the max.
Faf du Plessis vs. Running Between the Wickets
Faf du Plessis' running between the wickets has been dubious. It's like he's channeling Inzamam ul-Haq. If he's not running himself out, he's running his partners out. No doubt that pressure plays a part in this, but there won't be much pressure on him in the final ODI.
Whether Du Plessis can get it right will be key. He's under pressure to get some runs, too. Whatever may happen, it certainly can't get as silly as it did on that fateful day during South Africa's World Cup exit in 2011.