Billie Joe Armstrong is still in rehab following his onstage relapse/flip out at the iHeartRadio Music Festival, but thanks to the magic of pre-taped television, he began his run as a mentor for Christina Aguilera on 'The Voice' last night. If you missed it, you can check it out here. If you have still yet to see the infamous iHeart onstage meltdown, you can also check that out here.

Follow this link to watch last night's The Voice episode with Billie Joe Armstrong as a mentor.

Here's the video of Billie Joe Armstrong's iHeart Radio Music Festival meltdown. WARNING: This video contains explicit language: