When they'll finally get engaged is a constant topic of speculation.

But , 49, and , 42, looked like brand new lovers with their ear-to-ear smiles at the 54th ACM Awards in on Sunday.

The Hollaback Girl singer lit up the MGM Grand Garden Arena with her glittering silver outfit. 

Loving couple: Gwen Stefani, 49, and Blake Shelton, 42, looked like brand new lovers with their ear-to-ear smiles at the 54th ACM Awards in Las Vegas on Sunday

The shining mini dress featured an array of jewels over her bust.

The 5ft6in No Doubt singer paired the retro '60s-style outfit with sultry fishnet stockings and thigh-high black boots.

Her blonde hair was done up in a high ponytail and fell in wavy locks over her shoulders. 

Eye-catching: The Hollaback Girl singer lit up the MGM Grand Garden Arena with her glittering silver outfit

Blast from the past: The 5ft6in No Doubt singer paired the retro '60s-style outfit with sultry fishnet stockings and thigh-high black boots 

Blake went with a more casual look than his partner, mixing a simple pair of dark blue jeans with a classy charcoal suit jacket and vest combo.

The Voice coach took full advantage of the more relaxed award show atmosphere to sip on a beer throughout the country extravaganza.

He and host Reba McEntire had a back and forth from his position in the audience as the event kicked off.

'And there's my buddy Blake Shelton, and I see you brought your own microphone with you,' she said during her opening monologue.

Golden locks: Her blonde hair was done up in a high ponytail and fell in wavy locks over her shoulders

The former husband of Miranda Lambert was holding onto his own microphone from his spot in the audience.

'You used to need me to help do you this,' he said, referencing past years when Reba had a co-host. 'And God knows Luke [Bryan] did,' he joked. 

'I just figured I would just—you good?' he asked, to the audience's laughter. 

Bantering hosts: He and host Reba McEntire had a back and forth from his position in the audience as the event kicked off

Furious performance: Later, Blake took to the stage himself for a passionate rendition of his newest single, God's Country, an ode to the sparsely-populated sections of rural America 

Later, Blake took to the stage himself for a passionate rendition of his newest single, God's Country.

He switched over to a more thematically-appropriate denim jacket for the song, while strumming his acoustic guitar.

The track is full of romantic rural imagery and serenades the sparsely-populated small towns of the US.  

His fellow Voice coach cheered him on from the audience. 

Totally absorbed: His fellow Voice coach cheered him on from the audience

Comparing boots?  Gwen commiserated with Dierks Bentley while Blake was occupied

Though Blake was the only one performing, Las Vegas must feel homey enough to Gwen, considering she has her Just a Girl residency at the Zappos Theater in the Planet Hollywood Resort & Casino.

The couple first made their relationship public in September 2016, and since then they've been nearly inseparable.

Blake's previous marriage to fellow country singer Miranda Lambert ended in 2015, and Gwen's divorce from Gavin Rossdale was finalized in 2016.

She shares three children with the Bush singer, Kingston, 12, Zuma, 10, and Apollo, five. 

2