Given overall stats, fair way of determining a winner?

Hello,

First time posting, been searching around to try and find an answer. Unfortunately, I have no idea how to word what I need to know, so I'm forced to ask.

Simplest example: Team 1 (80 overall) vs. Team 2 (70 overall).

I'm trying to create an algorithm to determine the winner, being as fair as possible. Team 1 would obviously need to have a little more weight, given their overall is higher, but that doesn't mean Team 2 should never win.

I'm not sure what the name for this logic is, but this is essentially what I'm trying to figure out for the game I'm developing.

Any help is appreciated.

Something more complicated besides Team 1 having to score at least 14.2% higher than Team 2? Or looking at the other side, Team 2 having to score at least 87.5% of Team 1's score?

Without scoring/goals for now. I'll be handling that afterwards. The very base is just figuring out a winner between Team 1 and Team 2, with the overall playing a part in determining the winner.

Essentially, the overall stat is the only one in the picture for now.