The 32-year-old said he is scared he will mess up things, reported Showbizspy.
"That will be the biggest role of my life. I hope I don't screw that one up. I'm really, really excited about it and I hope to slow to down a little bit when the little person comes into the world," he said.
The actor also said he has been lucky when it comes to making it big in Hollywood
"I've been lucky, I've said it before, we work so hard on every single movie and you never know which ones are going to work and which ones aren't... I think it's just, you've got to keep doing stories you love and characters that you love," he added.