Naruto Episode 126: Showdown of the Strongest! Gaara vs. Kimimaro!!
Episode 126 of 220 of Naruto, aired March 16, 2005, 25 minutes. Available with English subtitles and dub where released.
Episode summary
Itching to fight and with a sense of guilt from the past, Gaara tells Rock Lee to stand down and let him take on Kimimaro. Meanwhile, Naruto continues on his quest to catch the runaway Sasuke.