Lady Gaga Debuts Dark Hair While Showing Off Bruno Mars T-Shirt — and Fans Think It's a Collab Hint

Lady Gaga has gone to the dark side.

The 38-year-old singer showed off a new dark brunette hairstyle, a drastic change from her previous bleach blonde strands, in an Instagram carousel.

In a selfie shared on Thursday, Aug. 15, the singer gave fans a close-up look at her fall-ready transformation. Her dark brown hair falls just below her shoulders and she kept her makeup look minimal with some pink blush and neutral lip liner. Her eyebrows are also noticeably still blonde.

The singer wore a black top, leopard-print coat and a pair of white sunglasses in the photos.

Gaga first revealed her new hair color in a Wednesday, Aug. 14 Instagram video. In the clip, the Grammy winner is seated at a white piano as she plays a few chords. Eagle-eyed fans noticed that at one point, the star tilts toward the camera to showcase the front of her oversize gray t-shirt, which features singer Bruno Mars.

Hours after "Bad Romance" singer's post, Mars, 38, shared a photo on his Instagram account of him wearing a Lady Gaga t-shirt. The coordinating posts are fueling rumors that a collaboration between the two artists is on the way.

"She made sure we saw the shirt," one user commented on Gaga's post.

"GAGA X BRUNO 👀 we are so ready for this Mother 🖤," wrote another.

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Last month, Gaga confirmed she was engaged to longtime boyfriend, entrepreneur and tech investor Michael Polansky, at the 2024 Paris Olympics.

In a TikTok posted by Attal on Sunday, July 28, Gaga can be heard introducing Polansky as "my fiancé" to French Prime Minister Gabriel Attal in the stands of a swimming event.

A source told PEOPLE that the couple got engaged "several months" ago.

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"The couple shared the happy news with family and close friends right away, but wanted to keep the engagement private otherwise," the source revealed, adding that Gaga and Polansky are currently planning their nuptials.

Gaga and Polansky were first romantically linked in 2020 when they were photographed kissing at a New Year's Eve party in Las Vegas. Just weeks later, they went public with their relationship during a PDA-filled weekend in Miami for Super Bowl 2020.

The singer sparked engagement rumors back in April when she was photographed wearing a massive diamond ring on her left ring finger.