Premier League cracks down on video
Football bosses are launching a crackdown on unofficial clips of action posted on social media.
The Premier League said using Vines and Gifs to capture goals and other moments is a breach of copyright.
During the World Cup, thousands of short videos were posted on sites such as Twitter within minutes of the ball hitting the back of the net.
Now English football's top flight is urging fans not to share the content.
Dan Johnson, director of communications at the Premier League, told BBC Newsbeat: "You can understand that fans see something, they can capture it, they can share it, but ultimately it is against the law.
"It's a breach of copyright and we would discourage fans from doing it. We're developing technologies like Gif crawlers, Vine crawlers, working with Twitter, to look to curtail this kind of activity."
Last year News International - now News UK- struck a deal with the Premier League to offer online highlights to paying subscribers to The Times and the Sun.
A Premier League spokesman said: "The use of Vines and Gifs to show Premier League football is a breach of copyright, and we would encourage fans to use legitimate means to access this content, such as the Sun or The Times goal apps.
"We are working with social media providers to take down pirated clips and hope fans understand the need to maintain the investment model that produces the football they love."
Dean Scoggins, deputy head of sport at the Sun, said the paper is working closely with the Premier League.
He said: "Posting poor-quality videos to social networks is illegal.
"It is breaking copyright laws and although the clips cannot compete with the quality of service that we are providing, we are not happy that it takes place."
Hundreds of thousands of users follow some football Vine accounts on Twitter.
Vine, which is run by Twitter, allows users to capture and share videos that are a few seconds long.
Gif, which stands for Graphics Interchange Format, is used for low-resolution football clips which are then posted online.
Adam Rendle, a copyright law specialist at Taylor Wessing, said any action taken against those in breach would probably depend on the scale of the infringement.
He said: "If it is just you or I on a Saturday afternoon doing it every now and again, I think the tactic there would be to inform Twitter or Vine and get it taken down on an isolated basis.
"If there are serial 'Viners' who are setting up accounts to repeatedly do this every time there is a high-profile match and they have got thousands of followers so it's becoming an unofficial service of goals, they might seek to get the account blocked.
"And if it is starting to get really serious, they might take an offline approach and start issuing proceedings."
The Premier League has faced long-running copyright battles over pubs that use cheaper foreign decoders to screen matches and free online streaming sites.
Mr Rendle said: "I think the problem from this (Vine clips) is anyone who has got a Sky subscription, a phone and a Twitter account could potentially be doing this. That's the real threat.
"The contrary to that is if you can get a relationship with Twitter and Vine to help stamp this out."
Twitter declined to comment but pointed to Vine rules which state that users "may not post content that violates the rights of a third party, including copyright, trademark, privacy, and publicity rights".
The most recent figures show that Twitter received a total of 9,199 copyright "takedown" notices in the first six months of this year - a 38% increase compared with the second half of 2013. Material was removed in 76% of the cases.
A spokesman for one of the most popular football Vine accounts on Twitter said: " The threat of legal action on the uploaders of these Vines we believe to be a scare tactic as the reality of policing this is incredibly difficult.
"The only contact we have had regarding these videos is from press outlets.
"We have had no legal contact of any sort regarding any of our communication. In the event this should happen, we will of course adhere to any instruction or guidance given to us by the relevant authorities.
"At no point whatsoever do we, as a team, upload the Vines ourselves.
"They are sourced from others across the globe who are regularly uploading content to their Vine account. We are merely posting what we can find on the internet that we believe our audience will like. We do this for our love of the beautiful game, not profit."