Kate Bosworth has a shot of whisky every time her favourite American football team scores a touchdown.

Speaking on 'The Tonight Show Starring Jimmy Fallon', she said: "I married into this team, my husband is a huge Dallas Cowboys fan as is his father so it's a family affair.

"We have an arrangement, my husband and I, every time they make a touchdown we take a shot of whisky, which I think is fair."

Talk show host Jimmy then joked that must mean the star and her director husband downed a fair bit of alcohol during the Cowboys' 24-20 victory over the Detroit Lions last week.

He joked: "So last week in the fourth quarter you did like three shots in 10 minutes or something like that?"

Kate replied: "Yeah … it was a good game. It was a good game!

"It was a nailbiter."

Jimmy joked the people of New York don't need to wait for their teams, the New York Giants or New York Jets, to score before downing some alcohol while watching football.

He quipped: "We have the Jets here and the Giants so we drink whisky no matter what."

But Kate didn't have any shots while watching the Cowboys take on the Green Bay Packers because she wasn't with Michael.

She wrote: "Without @michael_polish this game, so no drinking going on... But celebrating none the less! @LimuElizabeth @dallascowboys (sic)"

While the blonde stunner was celebrating early on in the game, she was ultimately left disappointed as her team went down 26-21 to end their chances of getting into the Super Bowl this season.

She wrote: "No matter the loss, no matter the call- I am so proud of this @dallascowboys team. They r Superstars who play their hearts out. #fanforlife (sic)"