Big Brother 16 HOH Twist

How does the new HOH twist work on Big Brother 16? Here's a rundown:

Julie informed the house guests how the HOH twist would work. Each HOH will nominate two house guests for eviction. When nominations are over, four will be in jeopardy of going home. In a Big Brother first, the battle of the block will take place. Frankies two nominees will battle Calebs two nominees. The nominees that win the competition, knock out the HOH that nominated them.