NBA rankings have generated a lot of conversation of late. To that point, ESPN ranked Tim Duncan ahead of Shaquille O'Neal. But which legendary big man was actually better? 

Well, there's a case for each. I talked to SI's Ben Pickman and "The Fantasy Exec" Corey Parson to get their takes.

Parson for Shaq: I mean, this is the closest one you can get right here, two of the all time great big men, as you know. What I will say is this though, I've got to give the slight edge to Shaquille O'Neal. When you look at his career resume, he's a four time NBA champion, three time finals MVP, Most Valuable Player award winner, 15x All Star. But you know what? Tim Duncan took a lot of that same stuff too. I think the difference is how dominant Shaq was offensively. He won the NBA scoring title twice averaging 29 points a game in 1995 and in the year 2000. Listen, Duncan is a great legendary basketball player, but going up against Shaq back in those days, when he was at the height of his fame, was almost like getting in the ring with Mike Tyson. He was so physically dominant and so gifted. I got to go with Shaq, but it's by the slightest of margins.

Pickman for Duncan: I was going to say the only thing that I think is clear about Shaq and his advantage over Tim Duncan is that Shaquille O'Neal is more excitable, has a bigger personality, is a more boisterous person off the court. Tim Duncan, he has five NBA titles. He has those two MVPs. That is one more than Shaquille O'Neal. And I think Duncan gets the slight edge for being a more consistent and all around better player. You look at the defensive end of the floor, the opposite end of the floor that Corey mentioned, Tim Duncan has fifteen all defensive team appearances, compared to Shaquille O'Neal's three. And he has eight first team, all defensive team appearances compared to Shaquille O'Neal's zero. They both had 15 All Star appearances and they were 15-15 against each other in postseason matchups. I think for Duncan's consistency and his all around game, I would give the slight edge to the Spurs legend.

Verdict: Both are right. Shaq was more dominant. He would dunk you into the crust of the Earth. 

Duncan was fundamentally sound, he helped his team in so many ways.

Ultimately, this might come down to peak vs career value. Tim Duncan was probably the better overall player because he contributed in a less flashy, yet plenty effective manner. But I don't know if any big man could handle Shaq Diesel at the peak of his powers.