Towards the end of last year we reported on Amazon holding talks to offer live sport through its Prime Video platform, and now the deal has been done. North America's National Football League has sold its streaming package to Amazon - the company will show 10 games during the course of the season, live-streaming the TV network coverage provided by either NBC or CBS.

The cost - about which both parties are keeping quiet - is estimated by a Recode source to be in the region of $50m. As part of the deal Amazon will also carry the network broadcasters' ad content, plus it has the right to sell a few ad slots per game.

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If that figure is even remotely accurate, it dwarfs the deal the NFL struck with Twitter last year - roughly the same Ts & Cs cost Twitter $10m. Industry observers have suggested Twitter's audiences were a fraction of those for NBC or CBS, but nevertheless Amazon has acted decisively.

Amazon has partnered with the NFL in the past, with the Prime-exclusive All or Nothing documentary. But this is a rare foray into live streaming for the company, and its first into the extraordinarily expensive world of major professional sport. "For us, this is about starting to bring live sports to our Prime members all around the world," according to Amazon's head of business development Jeff Blackburn.

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Twitter, however, seems undaunted by having lost out to to Amazon this time. It's been reported in the Daily Telegraph and elsewhere that Twitter is seeking tie-ins with the likes of BT TV and Sky to live stream some of their sporting packages, including Premier League football.

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