There is a troubling issue at the heart of The Blind Side. Not the fact that a privileged white family adopts a black boy from the projects to give him a better life. Not that it features one of the most annoying children ever to appear on celluloid. No, the most troubling issues for UK viewers is why American football is such a popular sport.

The Blind Side, which won Sandra Bullock an Oscar for best actress, follows Michael, a gentle giant man-boy from a broken and impoverished family as he fortuitously gets accepted on a scholarship to an all-American, completely white, high school, and then gets taken under the wing of the kindhearted Tuohy family. The Tuohy dad owns a string of Taco Bell franchises but it is the matriarch Bullock – an interior designer – who wears the trousers.

Michael is cajoled into doing his schoolwork and then introduced to American football, which he soon excels in thanks to the encouragement of his new family and his protective insticts that manifest themselves into his role as left tackle, responsible for protecting the blind side of the quarterback.

The Blind Side is very saccharine sweet, and is so American that many of the jokes fall flat with a British audience: “Who would’ve thought we’d have a black son before we met a Democrat?” would I’m sure have got a belly laugh in a US cinema, but was greeted with silence in Bristol.

It may be very American and feature an unintelligible sport to most of us from this side of the pond, but The Blind Side – based on the book by Michael Lewis – is one of those rare films about sport that are actually worth watching.

The Blind Side is showing now at the Orpheus.