Jennifer Garner says the 'Daft Day' cast were turned into Cleveland Browns fans after filming.

The 41-year-old actress stars opposite Kevin Costner in the story which follows the American football team on the first day of the NFL (National Football League) draft and insists the team's fans who were needed during shoots were so enthusiastic that it rubbed off on them.

She told ''We shot something where we needed Cleveland fans to show up in body make-up and in their Cleveland gear. So many people showed up. We needed them to stay for a full day - 12 hours - standing outside. They showed up, they cheered every take. It was more about keeping them tamped down than it was ever needing to say 'OK guys, Sorry, just to match your energy from 5 hours ago we need you to boost up.' We never had to say that. They were good to go. Their love for the Browns was so huge it turned us all into Cleveland Browns fans for sure.''

Garner also gushed about her co-star Costner, who is loved by everyone.

She added: ''In Cleveland he went to a baseball game one day, just quietly sitting by himself up at the top, the bleachers, eating peanuts. Eventually the camera found him, when they showed him on the tron - whatever that thing is - the whole place stood up and cheered for him.

Everyone is a huge fan of Kevin Costner's, he's just beloved.''