Julia Roberts felt "terrible" knocking over Meryl Streep in 'August: Osage County'.
The 46-year-old actress, who plays Streep's on-screen daughter Barbara in the gritty comedy drama, was forced to push the 64-year-old star- who plays Violet Weston - to the ground in one scene, which she admits left her feeling guilt-ridden.
She said: "It was horrible, I felt terrible every time. I was so worried about hurting her and she was such an incredible trouper. We did the scene for like an entire day.
"We're both bruised up and battered and I was like, 'Look at this! Oh my God, I'm just beating up Meryl Streep!' But she never said a word and she is secretly icing her swelling wrist, like nothing happened. She's asking me, 'What's happening to you?' She's more concerned about others and she has a lot more endurance than I do. I love her."
The brunette beauty felt "privileged" working opposite the 'Iron Lady' star and she couldn't help but feel admiration while watching her in action.
Speaking to HELLO! magazine, she explained: "Well, she is the best there is. She is really phenomenal and to watch her up close doing her thing - you're in awe. I, like, everyone asked myself, 'Where does it come from? How does she think of this stuff?'
"To get to watch that up close and to see her be a real-life person, actually working really hard to be that great, it was a privilege."