March Madness – the main season for U.S. college basketball – generated $1.24 billion of TV ad dollars in 2016 according to Kantar Media, making it the second most valuable post-season sports tournament in the U.S.

And while advertisers in the sports arena always want to go where the eyeballs are, they may want to shift their attention to social media, which has the potential for greater reach than TV, according to one expert.

Ophir Tanz, the chief executive of Gum Gum, a technology company that analyzes the images posted on social media and correlates them with brands, claims that the potential of social platforms in sport has been hugely undervalued. Gum Gum works with some of the teams in the NBA basketball league – which itself generated more than $1 billion in TV advertising in 2016 according to Kantar Media - to understand the impact of social media posts and put a monetary value on them.

"What we found is really quite striking. If you are a rights holder or team, we have been able to show that in most cases the exposure that's being obtained on social is nearly equivalent and sometimes more than television," he said during a panel led by CNBC anchor Carolin Roth at Advertising Week Europe in London this week."

"TV is definitely not dead. I'd say there is still in many ways more sponsorship value to be extracted from that medium, " he added."

"At the same time, there has been a dramatic undervaluation of the exposure that social is providing - effectively if you can't track it and prove it then it doesn't really exist."

For Nick Pinder, head of partnership marketing EMEA at the U.K.'s Manchester City Football Club, being able to quantify the value of social media is relatively new.

"We work with analytics companies to be able to quantify and to be able to put an accurate measurement on the growing social phenomena which hasn't been the case in recent years. The strides we have been able to make have been significant, moving away from that typical model where it is driven by broadcast and driven by those numbers," he said during the panel.

Manchester City's streamed its women's team's first UEFA Women's Champions League game on Facebook Live, in partnership with car manufacturer Nissan last October. Pinder said the engagement from fans was "extremely impressive." Player Yaya Toure also used Snapchat spectacles to show people behind the scenes at City's Etihad stadium in January 2017.

The value of a sports team or brand is something rights-holders work hard to quantify. Tim Ellerton, commercial director of Team GB, the U.K.'s Olympic team, is currently looking at this. "We've just put out a piece of work to really get to the crux of what the values of our own channels are and what that could mean to current and hopefully potential sponsors as well," he said during the panel."

"It will allow us to have a very sensible conversation with a partner when we put a number down on the table about what we believe our rights are worth, and hopefully we can verify it. It also allows that conversation when they go back to their CEO or CMO [chief marketing officer] to get sign off, do they actually understand what joining up with a brand like Team GB will actually mean for the short, mid and long term."

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