[GAMEPLAY] Different interraction between blitzcrank's grab and tristana's jump

So i was playing botlane with a friend of mine, i adc vayne and he blitz supp, vs tristana/blitz. What happened is that when my blitz grabbed tristana, she was able to jump away WHILE grabbed. I knew that tristana can avoid blitcranck's grabs by starting to jump BEFORE she get grabbed, but the animation that occurred was totally different, it was like she could just W away at any time during blitzcranck's grab.

This weird interraction occurred twice in the game.

Has it happened to anyone else?