My twitter was overloaded with Braves fans posting pictures of potatoes. Looked into it a bit and started an entry, but I could use some help fleshing things out. Pulled together some samples in the image gallery, but there are plenty on Twitter that I haven't pulled. Easy to find--searching "rally potato" or "#RallyPotato" will get you what you need.
On a separate but related note, has anyone looked in Joe Kelly Pouting yet, either as its own entry or as a subentry to the Astros Sign Stealing Scandal entry? The gist is that LA Dodgers pitcher Joe Kelly got ejected earlier in the season against the Astros, making a pouty face after he struck out an Astros batter. It got a lot of press and generated a lot of images, art, and crossovers with other memes, as well as large mural that Kelly himself visited. Even when looking at Rally Potato stuff, I saw a few iterations of that:
So it's still going on and could probably use an entry or subentry if anyone's willing to split the research & writing, or else has the time on their own.