to have to deal with a lot of people who are criticizing or attacking you

Every day they had to run the gauntlet of hostile journalists on their way to school. 每天去学校的路上他们都要受到一群不友好的记者的围追堵截。

to agree to fight or compete with someone

to invite someone to fight or compete with you

A price war looks likely now that a leading supermarket has thrown down the gauntlet to its competitors. 一场价格战似乎一触即发，因为一个龙头超级市场已经向对手们发出了挑战。