In sports, as in life, there is what you must do and then there is what you should do.

For now, nothing legally obliges Vin Lananna and the leaders of the 2021 world track and field championships in Eugene, Ore., to surrender their prize and re-enter a formal bidding process next year. Their small city remains — paradoxical but true — a fine and bold choice for this major event and the only vehicle available at the moment to bring it to the still-vital United States market.

But in view of the circumstances and in light of track and field’s shattered credibility, handing it back would be a strong signal that the sport is truly serious about embarking on a more transparent path, one in which too much power and influence no longer rests with too few.

“I think that would be very, very natural,” Bjorn Eriksson, the former head of the 2021 bid team from Gothenburg, Sweden, said in a telephone interview. “I would be happy if Gothenburg would try a second time, just for fairness and justice.”

The United States, long the dominant nation in track and field, has never staged the world outdoor championships, which began in 1983 and are the sport’s leading non-Olympic event.