In what seemed to be a subtle nod to the big news, the actress shared one of her headshots and captioned it "Poker Face."
Followers immediately picked up on the reference to the Mother Monster song.
"I see what you did there…" one follower wrote along with a few clapping hands emojis, which earned a like from Guzzardi.
"Girl, I'm warning you do not take a jab at Gaga," another added. "Her fanbase will eat you up."
One even claimed Guzzardi should form a relationship with Gaga's A Star Is Born co-star.
"You're beautiful. You should date Bradley Cooper," the commenter wrote, later adding, "Just kidding."
While Gaga and Horton have known each other for quite some time, an insider told E! News things only "turned romantic recently." The Grammy winner and the audio engineer sparked romance rumors this week after they were reportedly spotted locking lips at a restaurant in California.