The pay-per-view showdown between Errol Spence Jr. and Terence Crawford for the undisputed welterweight championship Saturday in Las Vegas is fascinating on many levels.

You can start with the fact that Crawford (39-0, 30 KOs) and Spence (28-0, 22 KOs) are two of the four best fighters in the world and go from there.

Here are 15 figures that might help illustrate how special this matchup is: