User blog comment:Omega natsu2/Fairy Tail Episode 198: The Golden Grasslands, Review./@comment-1359322-20140906045803/@comment-7418318-20140906080906

I still hang on to the theory that Motherglare let itself be distracted by F-Rogue being punched off of it's back and Atlas Flame used this opening to hit it hard enough to sent it smashing into the ground.

Whether it hit the Gate by chance or design is anyone's best guess though.