Your tap root, the one that grows straight down, likes room to grow. The plant will grow OK probably... I think I read that in order to sustain the plant, the tap root should be at least 4" long.
I'm betting that it'll grow wide, rather than tall, like when they're grown in party cups(for too long ). Those are always tall and narrow, because the roots didn't have room to spread. I think it'll do just fine, not optimum, but good, nonetheless.