Related Video: Delta happy for ex Brian
While speculation previously linked the singer to fellow judges Seal and rocker Joel Madden (who is married to Nicole Richie), it has now emerged that Delta is actually dating the host of the program, Darren McMullen.
The duo was spotted at Lady Gaga's Wednesday night concert at Sydney's Allphones Arena, joining Nicole Kidman's 45th birthday crowd which also included Nic's husband and 'Voice' judging alumni, Keith Urban.
Witnesses at the concert said the couple was distracted at the show, kissing and holding hands for all to see.
This romantic development has comes off the back of six-year friendship for the pair.
Reps for both have refused to confirm the relationship.