Lady Gaga and Bradley Cooper scooped the first prize of the night at the 61st Grammy Awards.
The pair won best pop duo/group performance for Shallow, the hit single from the musical drama film A Star Is Born, which stars Gaga as an emerging pop star and Cooper as an ageing rocker.
They won in a category including Christina Aguilera and Demi Lovato for Fall In Line, Backstreet Boys for Don’t Go Breaking My Heart and Maroon 5 and Cardi B for Girls Like You.
Accepting the prize on stage at the Staples Centre in Los Angeles, Gaga paid tribute to Cooper, who could not attend due to being in London for the Bafta film awards ceremony earlier in the evening.
She said: “I wish Bradley was here with me right now. Bradley, I loved singing this song with you. If I don’t get another chance to say this, I just want to say I’m so proud to be a part of a movie that addressed mental health issues, they’re so important.”
Gaga also urged anyone who suspects someone may be struggling with their mental health to intervene.
She added: “If you see someone that’s hurting, don’t look away.”
Host Alicia Keys opened the 2019 Grammys with a show of girl power, introducing Gaga, Jennifer Lopez, Jada Pinkett Smith and Michelle Obama on stage.
The show had been criticised last year for its lack of female nominees after women were largely ignored in the major categories.
It was markedly different his year, with five of the eight album of the year nominees being female.
To huge cheers inside the Staples Centre, Obama, the wife of former US president Barack Obama, addressed the crowd.
She said: “Music has always helped me tell my story and I know that’s true for everyone here.”
Obama added: “Music helps us share ourselves, our dignity and sorrows, our hopes and joys. It allows us to hear one another to let each other in.”
Camila Cabello, who was nominated for three awards, opened the show with a lively performance of her hit single Havana along with rapper Young Thug, before Ricky Martin joined them on stage.
Earlier, during the Grammy Awards Premiere event, the Arctic Monkeys missed out on the best alternative music album for their effort Tranquility Base Hotel + Casino.
The prize instead went to American singer-songwriter Beck for Colours.
Best music video was awarded to Childish Gambino, also known as Donald Glover, for the politically charged visual counterpart to his hit single This Is America.
Quincy, the documentary about revered US musician Quincy Jones, was named best music film.
Pop solo performance was awarded to Gaga for Joanne (Where Do You Think You’re Goin’?) while pop vocal album went to Ariana Grande for Sweetener.
It was Grande’s first Grammy win and writing on Instagram, she described it as “wild and beautiful”.
She also addressed her row with the Recording Academy which led to her not appearing at the ceremony, telling fans, “I tried and still truly wished it had worked out”.
Producer of the year went to Pharrell, who won ahead of Kanye West.