This UFC fighter's aim was a little low and it left his opponent in serious pain

Talk about a tough night.

https://vine.co/v/5WBaAmtiqPm

UFC Fight Week kicked off a three-night slate with one heck of a card from Vegas.

In the undercard, Gilbert Burns matched up against Lukasz Sajewski, and the highlight of the bout was this unfortunate shot below the belt.

Sajewski proceeded to get submitted with just three seconds left in the round.

Imagine getting hit below the belt, then getting submitted. Talk about a bad night.