900-some beating an 1800

I won the first round game at Cychess when my opponent who I play almost weekly at the local club took a 0 point bye so I played an easier opponent so I had 1 win and the opponent had 1 loss.

I may have been a bit disrespectful after I made the mate by just sticking my hand out and I put my self in a little scare just trying to stay up against him... the final position looked a little like this:

I was amazed that I won and reached 2-0, following with a loss to a 1600 taking me out of getting first place getting only the U1000 prize.