Def Leppard singer backs Taylor Swift performance

Some said Swift's performance of the first line was "breathless."

Elliott told Rolling Stone, "What a lot of people don't know, because they're not supposed to, is, she was up for five awards; two of them with us, and three on her own. She won three of them, and about a minute before we started that song, she had just picked up an award. So, after she accepted the award, she had to run down the stairs, run back to her dressing room, and change her clothes."

As Swift ran back towards the stage, Elliott said the director started counting down to the live performance. "Literally, she's running up the ramp, trying to put her in-ear monitoring in and clip the pack to the back of her skirt, so she can try to sing this thing," said Elliott. "She was really a busy girl that evening. All we had to do was watch, and then wander out and get ready to perform this song. People said she was a bit breathless on the first line, and that's why she was."

Swift won two awards that night and also performed an opening humorous rap with T-Pain, which has received a lot of attention.