Randall Garrett

“ He leaped in suddenly, and his fist smashed against Larry's face. Larry rolled with the blow, but it brought the taste of blood to his mouth.
His feet moving fast, the Earthman bobbed back away from the giant. He felt a glow of pleasure within himself. Here was his chance to practice a little with a Dornellian! What better training was there for a championship bout than a barroom brawl? He had to watch out for those claws though—those deadly razors that sprouted from the Dornellian's fingertips. ”

“ Larry heard an Arcturian spider-man click his mandibles together and whisper: "Yes, let the Earthman fight it out by himself."
Larry wasn't too worried. He had fought to the death on half a hundred planets, and hadn't been killed yet. An ordinary Dornellian didn't bother him much. He moved in confidently for the knockout.
His fist lashed out, but his opponent was even faster. Larry connected with nothing but empty air, and the Dornellian's claws raked down his side as the other hand slammed against the side of his head. ”

“ But in spite of the blood, Larry had finally gotten the measure of his opponent. The eight-foot giant weighed close to five hundred pounds; his mass was too great for him to be able to handle his body rapidly, no matter how fast his reflexes were.
Larry moved in again. He planted a hard right directly in the giant's throat—there had to be nerves there. The Dornellian gagged and dropped his head. Larry smiled and slammed his fist into the giant's rib cage, doubling him up even more. He could almost hear the crowd cheering now as he moved in for the kill. ”