"#GirlMostLikely premiere. Big night for @JayMacch - Great job, my girl. Congrats!!" the 51-year-old, former teen idol tweeted Monday night.
E! News said Macchio posed for photos with Julia on the red carpet during the Cinema Society and Brooks Brothers party at Landmark's Sunshine Cinema.
"She has a little part in the movie she got all by herself -- not through me!" Ralph Macchio told People.com.
"I didn't want any help from him. It was so much fun and a great first experience. Kristen [Wiig] is so nice, and everyone was so nice. I had one scene, but it was a great experience," Julia said.
Also attending the premiere were the film's stars Wiig, Darren Criss and Matt Dillon, along with producer Trudi Styler.