I don't think Yao is consistent enough to be ranked that high yet. He may very well be at the end of the season, but not right now. Another knock on Yao is his minutes. His current condition only allows him to play 20+ good minutes. Until he can play 35+ good minutes night in and night out, I don't think it's fair to put him up there.
Well, I thought some of them, Robinson is clearly not in the competition. His stats just aren't there. Duncan is a PF, and Mutombo didn't play more than 10 games.
Tim Duncan. He plays the low post in the san antonio offense like a center. His game is essentially that of a center's, not a power forward, an anchor on both sides of the court. He is a power forward in name only. ~Heretic~
My choice wasn't on the poll, so I am writing in Shaquille O'Neal. That would be behind Tim Duncan. Yao would be third.
If this poll is talking about right now, Vlade Divac is the 2nd best center. He has great all around skills. Good defender, great flopper. Extremely good passer and good scorer. Ben Wallace would likely be third. He isn't 2nd because of his lack of offense. Yao will be 2nd or 1st ina season or two, but he isn't there yet.
Right now, Yao is not the second best center. Yao is physically tired. He always gets worn out by the fourth quarter. Yao is not aggresive. He is very inconsistent. He is clearly not the best second best center. In 2-3 seasons, he will be the second best center. Right now, he is not.