February 20, 2014 14:36:00 GMT
The 'Piece of Me' singer forgot to lift up her microphone in time to sing the relatively new set.
Britney Spears went through a technical glitch at her Tuesday, February 18 concert in Las Vegas. Eagle-eyed fans noticed that she forgot to sing when her track "Alien" has begun playing.
In a video captured by an audience, Spears was busy waving to the crowd when her vocal track began before she lifted the microphone to her mouth. Soon after, she realized that she missed a few words and tried to catch up.
This is not the first time the 32-year-old singer has been caught lip-synching to her songs during her Las Vegas residency. A fan once filmed her singing without her microphone plugged in. A vigorous dance move sent the mic pack flying but Spears' vocal remained unaffected.
"Alien", a track from her eighth studio album "Britney Jean", is a relatively new set for Spears. She performed it live on February 12 for the first time since she kicked off her two-year residency last December.
Spears' rep has not given any comment.