Usher, Adam Levine and Shakira are on the judging panel for the show’s sixth season. (Trae Patton/NBC)

Yeah, yeah, “The Voice” is nice and all, we get it … giant red spinning chairs, contestants who can really sing, judges who actually like each other, etc. But far and away the best part of Monday night’s  season 6 premiere? When coaches Blake Shelton, Shakira, Usher and Adam Levine performed a medley in which covered each other’s songs. Lessons learned:

Blake Shelton did a strangely solid take on Shakira’s hip-shaking “Whatever, Whenever.” File that away for future concerts, Blake.

Shakira (wearing jeans and a flannel shirt for the occasion) singing “chew tobacco, chew tobacco, chew tobacco, spit” is a new highlight of the existence of Blake Shelton’s “Boys Round Here.”

Usher, not surprisingly, sounds heavenly crooning the first few lines of Maroon 5’s “Love Somebody,” and showed off some of his classic dance moves.

If the (suddenly clean-shaven) Adam Levine had started one octave higher in the beginning, his version of Usher’s “Without You” would have been perfect.