The Fifty Shades Freed actress, 28, and her Coldplay frontman boyfriend, 41, headed to the TD Garden in Boston on Saturday evening to catch a concert performed by Radiohead.
Martin, sporting a beard and dressed casually in a trucker hat and T-shirt, laid low with Johnson, who wore a tan coat with her hair tied up in a loose bun. With her bodyguard by their side, the couple remained seated for most of the show, with Johnson frequently leaning her head onto Martin’s shoulder.
“They stood up for a couple of the ovations,” a fellow concertgoer tells PEOPLE, adding that Radiohead’s 1995 song “Fake Plastic Trees” got Johnson on her feet. “I think she’s just reserved.”
Earlier in the evening, the couple was spotted strolling hand in hand.
Johnson has spent significant time in Boston in recent years, having starred opposite Johnny Depp in Black Mass, a 2015 film about legendary Boston crime boss Whitey Bulger.
In June, a source told PEOPLE that the couple appears to be taking their relationship to the next level as they get to know each other away from the spotlight.
“For the past two weeks, they have spent a lot of time together,” said the insider. “Chris lives in Malibu and Dakota seems to love hanging out there. They occasionally go for dinner with friends, but mostly have friends over at home. They go to the beach together, and walks around the neighborhood. They seem to enjoy sharing a quiet life. It does seem they are getting more serious.”
The actress and the musician first sparked relationship speculation after being spotted on a mid-October sushi date in L.A., getting “cozy, laughing and affectionate” during their one-on-one dinner, a source said at the time.
About a month after they were first spotted together, Johnson was photographed hanging out in the sound booth at Coldplay’s concert in Argentina. Fans in the crowd spotted the actress and excitedly posted pictures on social media during the show.
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Since then, the two have been spotted on dates around Malibu and Los Angeles and even arrived hand-in-hand to Ellen DeGeneres’ 60th birthday party in February. The two were seen holding hands as they caught up with Drew Barrymore outside the bash, which Martin’s ex-wife Gwyneth Paltrow also attended with boyfriend Brad Falchuk shortly after announcing their engagement.
Johnson has a history with musicians, having previously dated model/rocker Matthew Hitt. The two had been on and off for years, but were last seen together in 2016.
Martin was last linked to British actress Annabelle Wallis. The two began dating in August 2015, and were often spotted together as the singer toured with his band.