The move isn't completely shocking. When the merger fell flat, Eccles was faced with the prospect of running FanDuel indefinitely rather than taking a reduced role (namely, chairman) that would have let him pursue a new venture. Clearly, he decided that his entrepreneurial ambitions couldn't wait any longer.

His departure also underscores the buzz surrounding eSports. As Eccles told Recode in an interview, conventional sports are in a "harvest mode" where the big players are entrenched. The eSports realm, meanwhile, is in a "growth mode" where there's plenty of untapped potential. It's easy to see why Eccles would be willing to leave the relative security of FanDuel, then. When major team owners are rushing to stake their claims and gaming leagues are making regular appearances on TV, there's a real chance that the right startup could hit the big time.