The Citizens star expressed frustration over two rejected penalty appeals and confusion surrounding Harvey Barnes’ winning goal.
Although Dias admitted Newcastle deserved their win, he insisted the league must provide clearer guidance on what constitutes a foul in the area.
"Of all the decisions, only the second goal we need to make it make sense. Where's the sense in their player pushing our keeper out of the goal? What are we allowing and for how long?,” Dias told Sky Sports.
“ It's more like sometimes you allow it and sometimes you don't so what can you do? In the second goal Gigi is being pushed outside his area and there is no consequence.
"I had the chance to see the review and I think it Barnes is pushing him away from the goal. We are so picky with certain contacts but then ones like this with the keeper, then they allow it. If this is the rule then fine. But then let us do the same. Back in the day it was a foul and now apparently it is allowed.
“It is one of them that when you lose people say you are trying to find excuses but today Newcastle were better. They deserved the win because of that. They were able to finish more chances than us. There needs to be a rule."