The pair were pictured smiling as they sat ringside and watched the fight together. According to E! News, the two "looked like they were having a great time."
The report continued to claim that they were "not overly publicly affectionate," however they did leave the arena together once the fight ended.
Their 'date' comes only one day after Efron and Bro posted matching photos on Instagram of a night out watching a Los Angeles Kings hocket game on Friday.
“@lakings in overtime #freehockey,” Efron captioned a selfie of him wearing a Kings hat.
The pair didn't post a photo together, but Bro also uploaded a photo of her wearing a personalised hockey jersey with her name on it, from the same game.
“Thank you @lakings for making my first hockey game something very special 🖤 I’m already a fan!” she wrote.
Efron was last linked to his Baywatch co-star Alexandra Daddario.