Who is a better boxer, Pretty Boy Floyd Mayweather or Manny Pacquiao?
That is the tireless question that has been asked in the boxing world by the boxing world for a couple of years now.
We can perhaps only guarantee an answer if the two arguably best pound-for-pound boxers face each other.
But it's still interesting to consider who would win if they step into the ring - a possibility that appears to be growing.
Should the fight happen, Pacquiao (53-3, 38 KO) and Floyd Mayweather (41-0, 25 KO) would each have a solid chance of winning by way of knockout. They both possess power and speed, and both are tireless fighters.
But Mayweather and Pacquiao each have certain qualities that set them apart.
Mayweather is undoubtedly one of the best defensive boxers the sport has ever seen. A counter puncher, Mayweather thoroughly blocks himself. This makes it difficult for his opponents to land their power shots.
Mayweather's shoulders are a tool in his defensive game which he uses as a barricade. His shoulder defense obstructs incoming punches that make his opponents miss their hard punches.
At 5'8, Mayweather also has a slight height and reach (26 inches) advantage over Pacquiao who is 5'6 ½ with a 25-inch reach. Mayweather's reach advantage, coupled with his speed, would allow him to more accurately land punches.
However, Pacquiao has dominated against much bigger opponents.
As the Filipino phenom has moved up weight classes, Pacquiao's performances inside the ring show just how ruthless he can be. He has power in both his hands and body and does not tire out when pressuring his opponents. Pacquiao throws fast punches at a high volume and slows his fighters down. When he slows them down, he doesn't just pace the fight, he continues to use his speed and stamina as weapons.
A potential fight between the two would be a tactical fight fan's dream. Pacquiao's opponents need to have a good chin and quick reflexes because his punches come at them from all angles. Meanwhile, Mayweather's immaculate defense is essential for a fight since Pacquiao's style is to immediately be aggressive once the bell rings.
Both Mayweather and Pacquiao have had victories over many common fighters. However, Pacquiao fought many of the same fighters after Mayweather had fought them, thus providing more study of the opponents' strengths and weaknesses.
Unlike Mayweather, Pacquiao appears to have improved much more steadily as his career has progressed. Meanwhile, Mayweather has spent less time in the ring due to personal issues.
Who's better? On paper, a very slight edge might go to Mayweather considering he's never lost a fight, and is so gifted defensively.
But the only way to truly answer the question is for the two boxing stars to settle the debate in the ring.