Can i get some opinions on my latest short story (FIRST PARAGRAPHS)?

The writing isn't bad but no boxer would hammer his sparring partner to the extent you have described and certainly not in a gym. If he did that then sparring partners would disappear and he would get an unwanted reputation. Secondly sparring partners would not be forty one years old. Change those things and you have a good story. It flows well and it has a certain style that is readable. Good luck with the story.