Megan Fox and Machine Gun Kelly's 'Big Argument' Left Her 'Very Upset,' Source Says

Split rumors have been swirling around the engaged pair as of late.

More details about Megan Fox and Machine Gun Kelly's tumultuous relationship are coming to light. As split rumors swirl around the engaged pair, a source tells ET that they "got into a big argument before his performance at the Sports Illustrated event on Saturday night." ET has reached out to Fox and MGK's reps for comment.

"Megan and MGK have a passionate relationship filled with lots of intense emotions, both good and bad, but after this fight, Megan was very upset," the source says. "She was initially supposed to come with MGK to the event and had a whole outfit planned, but she backed out last minute."

According to the source, the apparent argument affected MGK's performance.

"MGK wasn't in the right frame of mind to be performing after this," the source says. "He wasn't himself and his band carried the show on their backs. It wasn't a usual MGK performance or what people expect from him. His mic died while performing 'Bloody Valentine' and he tapped it and seemed annoyed before someone came to replace it."

It also meant that MGK was unaccompanied as he left the venue. "Usually after a show, it has become routine for MGK and Megan to walk out together with the band, but on Saturday night, he was alone," the source says.

After the concert, the source says that MGK and his band performed at a local bar.

"He seemed to be a little bit better, but still chaotic and distracted," the source says of MGK. "The band was laughing, jumping on each other, and trying to act normal."

Split speculation around the couple began earlier this month when Fox posted cryptic lyrics on Instagram. Around the same time, fans discovered that the 36-year-old actress no longer follows her fiancé on the platform, and has deleted photos of him from her account. Fox, who was spotted out with MGK throughout Super Bowl weekend, later deactivated her account entirely.

"Megan and MGK have a very intense relationship with lots of highs and lows. They have a tendency to get into arguments and then end up making up," a source previously told ET, before noting that Fox "likes to troll her fans during the more 'off' times between them for attention."

The pair, who got engaged in January 2022, made their most recent joint appearance when they stepped out at the 2023 GRAMMYs, where the 32-year-old singer was a first-time nominee. After he lost to Ozzy Osbourne's Patient Number 9 for Best Rock Album, Fox praised him in an Instagram post for handling the process with "grace" and "maturity."