Where once expansion meant building stadiums, adding teams and landing broadcast TV contracts, the NFL, NBA, and others have turned to social media to reach fan followings in foreign countries.

The NFL teamed with Twitter to live stream 10 games this season worldwide for free (after testing the approach with Yahoo for one game a year earlier.

And when it sought to stream games in the burgeoning Chinese market in which Twitter is blocked, they turned to social media service Weibo.

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