Well first of all it's Messi and Ronaldo, it's not even close. Y'all are crying about Kobe/MJ/LBJ/GOAT... debate, I'm from Africa and I guarantee you even kids that barely seen them played are arguing about who's the best between both
Then you have Usain Bolt and Roger Federer that are known enough to be in the like of "pop culture", people doesn't know the X and O's of their sports but everybody will watch Olympic final of 100m just for Usain Bolt and same as for a Nadal-Federer final in a grand slam. I also can bring in that part Tiger Woods but just as a name, whole bunch of people don't know **** about golf (myself included).
As for basketball, everybody knows Michael Jordan as a name/brand/achievements, waaay behind but just like that I would say there's Magic Johnson that many old folks can name also. Shaq because of... you know he is Shaq, an entertaining funny 7 footer. But I would classify him as part of popular culture altough, him, nobody will give a **** about his sports career but you know when he had his dive session in the public with Suns it was shown on primetime national news here in France or when many website/TV shows around the world are showing his dance move in ASG warmup or his ASG introduction with jabbawokeez.
LeBron and Kobe are known by people that give a little **** to basketball in Europe for example, but I can guarantee you that LeBron or Kobe comes in a little town next to mine in France and people will say nothing other than "It's one big black dude !". But if Cristiano Ronaldo or Lionel Messi are doing the same to some **** hole in many country of the world, in the mighty words of Kaiser Chiefs : "I predict a riot".












