Filipino congressman Manny Pacquiao will be facing Mexico's Juan Manuel Marquez Saturday night for the fourth time at the MGM Grand in Las Vegas (HBO PPV, 9 p.m. ET/6 p.m. PT), after beating him twice and fighting to a draw in the first three fights.

The legitimacy of those results, however, has always been debated, transforming each of the judges' decisions into an unending controversy. This time, without any titles at stake and with both fighters closer than ever to retirement, Pacquiao will be looking for a definitive victory that could dismiss doubts about his superiority.

Here are five keys for Pacquiao against Marquez:

Do your math

Over the speed limit

Dancing like a star

Far from danger

Pack an extra plan

Bernardo Pilatti is a contributor to ESPNdeportes.com.