Tom Petty's 'I Won't Back Down' was sung by contestant Dia Frampton and her coach, country star Blake Shelton, during the final competition show of 'The Voice' tonight.

"It's the perfect song to sing on this last show," said Frampton of the 'Full Moon Fever' cut before to the performance. "'I'll stand my ground' is the perfect last lyric I'll want to finish on."

The duet featured Frampton and Shelton each playing guitar while dressed in matching black suits and sunglasses. Frampton has a smoky-sweet voice that paired nicely with Shelton's deep country twang.

On Wednesday's final results show, the one and only Stevie Nicks -- Petty's own duet partner on 'Stop Draggin' My Heart Around' -- will perform on 'The Voice.'

Watch Blake Shelton and Dia Frampton Perform 'I Won't Back Down' on 'The Voice'