"He thinks that he's a great singer, but he's really awful! And I don't ever want to tell him!" she laughed. "I'm always like, 'Honey, you should pursue it! Pursue it -- pursue your country album!' He's really terrible. But it always makes me laugh. I can't help it!"
The 34-year-old actress -- who stars opposite Chris Evans, Dave Annable, Joel McHale and Zachary Quinto in the rom-com -- flew solo at the premiere, as Pratt was busy promoting Moneyball in Oakland, Calif.