When people are afraid, no one will dare to make an advance. However, a little nudge of encouraging words is enough to provoke their spirit.
It was what Belen had aimed. A little speech he had given after his battle with Basil had been intended to provoke a certain 'idea' in their minds. Surely, Belen wasn't just encouraging the other participants. He wasn't such a person.
The idea he had subtly conveyed to their mind was simple. He had basically told the other participants to gang up on Basil. With the rule stating the fight should be one on one, this should be impossible. However, everyone had two chances.
It was one of the time where they had to work together for the greater good. They could use one of the chances to have an unrestrained match right off the bat, and forfeited as quick as they could just to annoy Basil, like what Belen had done to Basil.