KEY POINTS:
Sir Isaac Newton's third law of motion states: Actioni contrariam semper et qualem esse reactionem: sive corporum duorum actiones in se mutuo semper esse quales et in partes contrarias dirigi.
Rough translation: If the Blues win but the Hurricanes get a bonus point then its all on for love and money.
Okay, the literal Latin translation might be some piffle about actions and equal opposite reactions, but Newton's law clearly applies to this weekend's tantalising Super 14 shakedown.
Three of the four fate-determining, final-round matches will be shaped by what happens elsewhere, in a stadium far, far away.
The exception is the first-up encounter between the Blues and the Hurricanes, which has the potential to either greatly clarify the playoff picture or to open up a realm of scenarios so vast the Deep Blue supercomputer would struggle to predict the final outcome.
A Hurricanes victory would confirm them in second, eliminate the Blues and leave the Waratahs, Stormers, Sharks and Chiefs scrapping for the final two playoff spots. Both the semifinals would then be played in New Zealand.
A Blues victory would expose the true tyranny of the bonus-point system, with the playoff picture being decided not by victories and losses, but by four-try hauls and narrow margins of defeat.
There are few certainties. One, however, is that the jostling for position will go right down to the final match when the Chiefs take on the Sharks in Durban in the early hours of Sunday morning.
The Chiefs may well be done and dusted by then but the Sharks will definitely have something to play for.
By kickoff there will be at least three teams with their feet up knowing they have done enough. But whether they will be in Auckland, Wellington, Sydney, or Cape Town, there will be some very nervous watchers as events unfold in Durban.
Whoever sits fourth will be praying Newton's third law of motion isn't about to bite them on the rear end. Because if the action is the Chiefs or the Sharks moving up to claim a semifinal spot, the opposite reaction will be that previously fourth-placed side dropping out of title contention with a thud.