Christina Aguilera's reaction when guest Justin Bieber approached to greet her on "The Voice" Tuesday night is causing a buzz on the web.

Bieber shook the hand of judges Adam Levine, Cee Lo Green and Blake Shelton but when he hugged and kissed Christina, she gave him an evil eye. (Watch the Video Clip Below)

Facebook was inundated with comments from people who criticized her "bitchy" attitude, saying she was "rude" to Bieber.

Read the posts from the most outraged viewers:

"Christina doesn't like the spotlight taken away from her! she can be such a snob--Justin didn't deserve her bitchy attitude!" one user said.

"Christina's face was priceless!!!!" another user noted.

"Yes Christina's expression was priceless. Priceless in the rude I am better than everyone category," another user replied.

"The Voice could go to hell if she keeps that attitude as many of us will not be able to stand her anymore..." another person wrote on the social network.

"Christina gave him a death stare, don't forget that part."

Yet, Christina had its supporters.

"Christina did the right thing by snubbing Bieber...the show was great before that and her reaction might have saved it from such a stupid guest act," one Facebook user said.

Watch the Moment Below:

Tags: Christina Aguilera