Interestingly you don't need to defend e4 immediately (whites move 4) because of the Qa4+ fork. However it is difficult to see what else to do since both Bc4 and d4 block the fork and lose e4. I probably would have played d3 as well.
I don't think 14.exf was the best because it brings his bishops into the battle quickly. It would be easier to defend the pawns and let fxe open the d file for you.
14.g4 was very dangerous for white since balck could start dismantling the King side pawns or simply attcak along the f-file which is now harder to defend.
Round about move 25 black should have doulbed on the f-file to make thtreats against f2-f3. Trading rooks its good for white becuase blacks are more active. In this sort of position black has to drop e5 and go for broke otherwise he'll get crushed.
30...h4 was the final straw for black who no longer has any real way to pressure g4 and white's King.
37.g5! was exactly the sort of move black should have made earlier: attacking at any cost.
44...Rxf is risky but has to be played otherwise black will end up a piece down and passive.
Over all I would say Black was scared of losing to an "officially" weaker player and this is why he lost. A finely played game by white.
Two weeks ago I played this match at my local club. As it started with 1. e4 c5, the opening I dislike against stronger players I am quite happy with the result. Besides that, it was a very interesting game to play, making it rather exciting for quite a while as both sides had the chances to win the match. I hope my first contribution is good enough. I added my own annotations to the match, talking you through my thoughts during the game.
Any comments are welcome!