Let's say Nehe Milner-Skudder doesn't scrub up from his left calf injury and the All Blacks need to find a replacement for the World Cup final.
Simple, most would say. Do as in the semifinal victory and shift Ben Smith to the right wing and start with Beauden Barrett at fullback.
That change brought some extra zip to the backline and a try which tipped the gruelling contest back in the All Blacks' favour.
It might not be as simple as that.
After the match, Smith was puffy, bruised and cut around his right eye while the side of his face was also swollen. They were the wounds of the All Blacks' aerial magician who was superbly safe under the high ball and even scuttled into the middle of the park from the wing to defuse another attacking kick from the Boks.
Smith's positional surety and safety under the high ball barred the Springboks attacking methods and reinforced the All Blacks assurance on an awkward afternoon at Twickenham as drizzly conditions hit the second half of the semifinal.
Smith is the side's premier fullback and where the selectors like him.
But if Milner-Skudder is out injured, has the other specialist wing Waisake Naholo recovered from his leg issues and is he ready for the pressure of the tournament decider?
The selectors could retain Smith at fullback and use Naholo, Barrett, Sonny Bill Williams, Malakai Fekitoa or Colin Slade on the wing.
Another option would be to begin with both Smith and Barrett - in whichever roles they felt best - and pick someone else on the bench.
The other possibility is a grim consideration but one the All Black selectors will have thought about in their "what if" scenarios.
Should Smith's facial injury count him out of the final and Milner-Skudder also fail a fitness test, the selectors would have to dig deep.
The former England winger opened up about his struggles post retirement.