It sounds like you are good with open guard, and tryign to work closed and the guy is trying to keep you form closing it... So why look to close it if that's specifically what the guy is fighting against?
That's silly, and goes against all the philosophy behind the art. If your open guard is so good you were actually tryign to work closed, but the guy tries to split it and lands in Ninja Base, just blow him out of the water with your open guard game.
That's like saying "I've got an awesome top game, so I was trying to work my guard, but once we start, everyone just jumps to guard on me. What do I do?"
Work your game, OR, tell the guy "Hey, I want to work *blank*.."
In this instance, say "Hey, I want to work my closed guard", and maybe he'll let you close it. Then you have to keep him from splitting it, which if your open is that good, he should maybe be looking to just posture and work something else anyway.