Taylor Swift's concert got a little buggy Sunday after she swallowed an insect during her Sunday "Eras" show in London.
The pop star hit the stage for the third night in a row at Wembley Stadium ... and during the 10-minute version of "All Too Well," there was a fly in the ointment -- AKA her mouth.
Check out the vid ... Taylor was strumming her guitar, standing at the mic, when suddenly announced she had swallowed the bug and asked the audience to pinch hit and sing the lyrics.