User blog comment:Berserkchart486/Chakra Levels!/@comment-25152698-20151006111929/@comment-25152698-20151006185358

Again, Gaara never used any tailed beast orientated abilities during that matchup. Look at Naruto vs Neji for example; Naruto didn't use Kurama's chakra until after all of his own was clogged up. So, Gaara was probably running low on his own chakra reserves. If he ran out completely, and because you are going so much into hypotheticals here, then Shukaku would've probably possessed him and smacked Kimimaro's ass.

But, it's like I said just moments prior. Kabuto was uncertain as to who was stronger between Part I Sasuke and Kimimaro. Realize, Kabuto stated this after Sasuke's curse mark was upgraded; even without the upgrade, Sasuke wounded Gaara twice; Kimimaro on the other hand, using his upgraded curse seal, didn't accomplish anything.

But, going back to Tsunade for a bit, it's all due to her that Rock Lee was even able to get a shot against Kimimaro; and even then, against an intoxicated Lee, Kimimaro couldn't do anything! Lee was already weak; Kimimaro could've at the very least finished him off.

Kimimaro couldn't defeat Lee (who wasn't using his Eight Gates) or Gaara (who wasn't using his tailed beast); Tsunade's reserves were large enough to feed her entire hidden village and more.