The track was one of a handful of recordings by UK acts to feature on the show, which was broadcast last night across the US by ABC. The programme, which has a huge reputation for lifting sales of tracks which it features, also used tracks by Adele, Coldplay, Bryn Christopher and Ida Maria in the closing episode. Some 21.5m people watched the show, according to Nielsen Media Research.

The use of Mercy comes in the week Duffy's debut album Rockferry, ...