2 liter soda bottles

So I have some homebrew in a 2 liter bottle. I was planning on taking it to a super bowl party today. Turns out that a bunch of people fell through at the lat minute and at most there will be 4 of us there, more likely just the 2 of us How quickly will that 2 liter go flat? I'm not too worried about it because I'm pretty sure we'll both be in a drinking mood. I'm just curious what kind of experiences people have had. I could bring 1 liters instead but then I don't know when I would ever drink that big boy. Ah who am I kidding, I can always find an excuse to drink beer.

How much head space did you leave and did you keep it refrigerated? I'd imagine it would last a few days if you didn't leave too much head space on it.

It'll last a day or two. However, it's not that tough to drink two liters of beer between two people. It's less than three 12 oz servings a piece.

just drink the beer, problem solved.

Ok, I was worried about it going flat much quicker than that. It will definitely be gone before it goes flat.