Gaara buries her alive...
Taijutsu is litterally useless unless if it is at insane speeds; and that would only be a matter of "challenge" to Gaara; not a certain victory. He can make the whole battlefield a sea of sand, which renders Tsunade's "punch the ground" attack useless. Or he can take flight with his sand; at this distance he is more than capable to do before an attempt of attack by Tsunade; he was able to save both himself and Lee at last second from Kimimaro's bone forrest (which spiked up at high speeds) and went air with sand.
Even with Katsuyu, he takes this without much change in trouble. That slug is for medical purposes mainly; and he has to take down Tsunade not the slug. The acid slime would be avoided by flight ability anyway.