Due to the rain Tuesday night, the line at Citi Field’s Shake Shack was short. I grabbed the opportunity to review the last remaining unreviewed Shake Shack sandwich.

It will set you back $6.50, if I recall correctly. Normally it will also cost you a couple innings of baseball, but not if you go a half hour before the game while they’re pulling the tarp off the field.

I think it’s even better than the Double Shack. While the single patty de-emphasizes the delicious, high-quality beef, it makes for a better balance of ingredients. Biting into it, you taste everything at once: crispy lettuce, sweet tomato, tangy shack sauce, creamy cheese, soft bun, juicy meat. It’s damn near elegant. No, screw that; it is elegant.

I’ve long since given up comparing sandwiches to baseball players but I think I’m prepared to make the following call. And this is not a distinction I would bestow upon a sandwich lightly: The Shake Shack burger is the Carlos Beltran of sandwiches. Deemed overrated by some but still appreciated by legions of Mets fans, every element of its game is excellent without being flashy. It will sometimes require a wait — diminishing its value, no doubt — but patient fans can recognize its greatness in center field at Mets games.