One of my favorite boxing rounds ever, the first Holyfield vs. Bowe fight, round 10:
https://www.youtube.com/watch?v=6GngvYoqQj4
I saw this on Pay-per-view back in the day, and I was jumping out of my seat. This was like a Rocky movie, except it was real. At :25 seconds into the video, Bowe clocks Holyfield with an uppercut, and he immediately smells blood and totally unloads on Holyfield with everything he has. Somehow, Holyfield doesn't go down and he manages to stay upright and hug Bowe to keep going. With 1:10 left in the round, Holyfield somehow gets the energy to let loose a barrage on Bowe (WTF!) and then with 15 seconds left, throws another big sequence of blows to end the round. Everyone stood up in applause - the people at the event, and the people at the bar. That was amazing live, I still get chills watching it. Holyfield was a dead man walking, and ended the round swinging. He lost the fight, but won my respect and everyone else's.