Major League Baseball has an age problem. The 147-year-old league is financially healthy, sure, but younger fans are increasingly hard to find. MLB has the oldest median TV audience at 56 years, compared to 49 for NFL viewers and 41 for NBA fans, according to Nielsen. But with a cadre of young stars eager to leave their mark on the game, baseball hopes to bring millennials back to the diamond. As Rob Manfred begins his second season as commissioner, he's looking to increase the league's social footprint while appealing to those who don't watch sports on traditional TV.