Ansel Elgort's mother embarrassed him in front of Bruce Willis.

The 'Insurgent' star was left red faced when he brought his mother along to an Academy Awards after-party, where they bumped into the 'Red 2' star but she had no idea who he was.

He said: ''Bruce Willis was there with his wife and they were introduced to my mom and she said, 'Oh hi, what's your name?' And he said, 'I'm Bruce.'

''And she said, 'What do you do? Your wife's a model.' And he said, 'I'm an actor.' And she said, 'Oh my son's an actor. How's that going for you?' And he said, 'It's going pretty good.' I was like dying.''

The 20-year-old actor also admitted he was nervous ahead of presenting the Best Visual Effects award at the Oscars because he was unsure how to pronounce some of the nominees' names.

Speaking on 'The Tonight Show with Jimmy Fallon', he said: ''I tried to pretend like I wasn't (nervous) but I certainly was. I was actually most nervous because I had to present Best Visual Effects and the people who make visual effects are really good at their jobs but they have really hard names to pronounce for some reason.

''Chloe Moretz, who I presented with, got to read all the names on the voice-over so she got to really see them and phonetically read them out but I didn't know who was going to win obviously. Whoever wins, it's four names...

''I looked at all the people who could have won and I'm freaking out and I said, 'OK, I really hope 'Guardians of the Galaxy' doesn't win,' because it was all four names that I couldn't pronounce. I didn't want to pull a Travolta. If I messed up at the Oscars, I wouldn't be invited back.''