Is this a sane encounter for my party?

[Corolinth]

I had the cleric, the paladin, and the ranger/fighter all fail their will saves against the DC15 confusion gaze in the first round. They had to have the confusion effect dispelled, and by that time they had run to the other side of the battlefield. They were invading a dragon's lair, and the spellcasters didn't want to waste spells on the very first encounter. Then on the way back into the fray, the ranger/fighter fails his will save again.

They made quick work of the thing once they finally got into the fray (hence why the spellcasters weren't going to waste spells). The problem was getting that first hit in.