You know a game has "made it" when it starts to appear in other games. As the video above demonstrates, modder Bounty4321 has managed to build something very similar to Rocket League in StarCraft 2, using WarCraft assets. It's only in alpha and isn't available on Battle.net as yet, but all you need to know is that it exists. That's enough for me.
You'll notice a few obvious differences: as the name suggests, Aqua League is set in a shallow pool ("I've always wanted to do a game that had something to do with water" the modder says on his YouTube page). Meanwhile, instead of rocket-powered cars you're controlling bipedal creatures. Doesn't matter in the end, because the objective is still to get a giant ball into your opponent's net.
"Its Nagas Vs Revenants in a battle to see who can please their God the most by scoring," Bounty4321 writes in the YouTube description. He says he started working on the concept before Rocket League, but conceded that he "won't deny that the game does take inspiration from it". I'm looking forward to checking the final build out, or at least watching other people play it.