Bob Johnson Memorial 2015 - Round 3

So I was going into this one with a win and a loss, both against players rated higher than me.  I was hoping for at least a draw in the final round, but it wasn't meant to be.  My opponent had 300 rating points on me.  I gave him a good fight, but I fell for another diagonal pin similar to the one that got me in Round 1.  (Tactic to work on visualizing, perhaps?)