I really liked your story, PN, hence its appearance on my long shortlist. I immediately got the running a book idea from the odds you showed, so I didn't even need the last line. (Go me!!) But a good title can add so much to a story that it's worth spending a little time on that alone.
The different formatting might have helped win over a few more members, as when something is dense, the eye tends to miss words unless we're reading carefully -- and when there are 40 or more stories that's not always a given. Spacing out gives a story room to breathe and helps to ensure a more thorough reading. For myself, though, I'd take the "I fire up my buzzsaw" sentence into the final para to give that last line a bit more punch.
I agree with TDZ about the comma splice in the first line, and as pernickity as that sounds, punctuation can make a difference between a mention and a vote for us pedantic types! Her idea about stakes is also a good one. I'd got that the narrator was perceived as the weaker of the two fighters, from the difference in odds, which was enough for me, but making it clear he/she is fighting for freedom would be an excellent way of creating empathy. I'd guessed it was a Hunger Games kind of thing so had already read that into it but it's always better to be more concrete so readers don't have to make assumptions. I invariably get my other half to read my stories, and almost as invariably I have to add bits to clarify the plot as he's left scratching his head.
As you say, characterisation is difficult in only 75 words, as well as getting a plot in there, but it gets easier with practice. Personally, I think this was a great story, and if you'd not said it was a first attempt, I don't think anyone would have been the wiser. Well done!