Board Thread:Narutopedia Collaboration/@comment-17623-20140206165340/@comment-4728499-20140208105627

Tailed Beast Rasengan is a Mini Tailed Beast Ball with rotation added to hold it together since Naruto couldn't use the proper version at the time, they are different but it became pointless before he actually got a chance to use it. Kabuto speculated since the Tsuchikage wasn't hitting as hard as he should while he was flying, just because Kabuto drew that conclusion isn't absolute proof, Onoki could just be physically weak as far as offensive ability is concerned due to age.