It's been the subject of heavy debate among seasoned gamers for decades, but now it looks like we can actually lay to rest the mystery of what Mario was doing to get Yoshi to stick his tongue out to grab stuff.
Until now, the general consensus was that Mario was gesturing in a kind of 'forward' signal with his hand - but the truth, it seems, is far more sinister.
Sorry to break it to you, but everyone's favourite little pixelated plumber was actually punching his dinosaur companion in the head that whole time. Shocking, I know.
The revelation was made by none other than developers Takashi Tezuka and Shigefumi Hino, so it's coming straight from the proverbial horse's mouth.
"However, the set up that I drew was that when Mario punches Yoshi in the head, the character's tongue shoots out in surprise."
But the plumber's dino abuse doesn't end there.
"What's more, there's an added 'bop' sound. However, it seemed like people would say, 'poor Yoshi,' so that's why it became that Mario is saying, 'go,'" Hino added.
Naturally, Nintendo fans on Twitter are aghast at the news and have taken to their keyboards to express their shock.
So, there you have it. Feel bad now? Because really, what that all means is that YOU have been punching poor little Yoshi in the head for all these years.
How will you sleep at night?