Later, Peyton: The new face of sports endorsements

The era of the mega-athlete sponsorship deal is coming to an end, some experts say—and the killer is social media.

"Social media is such a huge component in the drive for a brand today," said Denise White, CEO of EAG Sports Management, which represents professional athletes. "There isn't a marketing deal that doesn't have a component of social media on it."

Many companies looking to secure sponsorships with athletes tend to steer away from the player with the most touchdown passes—they want the player with the most Instagram likes.

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According to Kyle Nelson, a software and social media entrepreneur and co-founder of MVP Index, which measures athletic social media brands, companies are more interested in the connection between the fan and the player.

"There are more people on social media than those watching TV," Nelson said. "These athletes are communicating with the average fan. [The fans] feel more connected. Millennials aren't watching TV shows. Instead, they spend more time following what they are passionate about."

One key part to this method is the type of athlete targeted. In many instances, the top-tier athletes of today's sports tend to separate their private and public lives—meaning they have little to no social media presence. Instead, the second- and third-tier athletes often garner the attention of the fanatics.

It's the latter athletes that are securing the sponsorship deals—all at a price significantly cheaper than a typical first-tier sports icon.

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"Social media is such a drive for brand," White said. "If companies can get a second-tier athlete with a huge following, they can drive the brand through social media. They are cheaper, yet they still have the social outreach that a Kobe Bryant may have."

A benefit to social media sponsorships is the method of advertising it provides. It eliminates the spam-like qualities of banner ads and obvious product placement and replaces it with approaches that seem more natural and organic.

"Carmelo Anthony and Seth Curry are huge golfers. How often do you ever hear them talk about golf and Callaway?" Nelson asked. "If you give them a set of Callaway golf clubs, how many millions of people on their Instagrams will see them use (the clubs)?"

Nelson's firm MVP Index ranks players by taking into account their reach, the number followers they have, their engagement, the number of likes, shares, retweets and comments they receive, and the positive and negative sentiments around each athlete based on what online sources are talking about. The maximum MVP Index score a player can receive is 1. Below is a chart of the top 10 football players, ranked by their MVP Index score, since week seven of the NFL season.

One of the more noticeable things about the list: no Peyton Manning and no Aaron Rodgers. Those two quarterbacks are arguably the two most recognizable figures in football.

Is this a signal to the end of an era? Will we never see another George Foreman grill? Ed Butowsky, partner at wealth management firm Chapwood Investments, seems to think so.

"I don't see that happening again," Butowsky said. "Unless the product is superior, you are not going to get market share. Back then, it was infomercials that fueled those products. It was a moment in time."

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A strong social media presence may usher in a new era of athletic sponsorships, but marketers will still have to look at an athlete's history and the ways they use social media, said Jack Brewer, former NFL safety and founder of the Jack Brewer Foundation.

"Character is first when you identify athletes. Find guys that aren't risk of tainting your brand," Brewer said. "Some athletes can engage in social media and really drive value, but you have to be selective. Some guys have more credibility than others. Some guys may be a jokester on social media and may not say anything that can benefit the product."