What concerned the human was the fact that not only did the tournament take place over a number of days, with a series of duels to weed out the majority of the competition before the grand melee to determine the remaining semi-finalists, but also the possibility he might also not get the chance to do the one thing that made him agree to that bloody arrangement in Canterlot in the first place. You see, he had learned a lot in that fight with Ferix, namely that the dragon was not the only person there who personally wanted the chance to grind Handy into the dirt. For bragging rights if nothing else. Additionally, the sight of the human bloodied and dirty went a long way to boost the confidence of said participants to do just that. He also learned that Ferix could shrug off most of what Handy could do, and Handy was pretty sure that if it came to a straight fight, the dragon would be the victor. Also, you know, his fire breath was something he was particularly concerned about.