I am trying to describe individuals who are watching a competition (e.g., any sporting event) but they are unhappy with how the result is going. Specifically, consider the subs of the losing team sitting on the bench. If they were happy, I would say they are cheering, but they are in fact very angry and disappointed because they are losing.
I could use "jeered" or "catcalled," but that is quite disrespectful, which usually the members of the same team would not do to each other; instead, they would perhaps be shouting angrily and disappointedly, but not in a rude way that perhaps fans might. So, something in between a cheer and a jeer.
e.g., The rest of the team looked on as yet another goal was missed, they got to their feet and ______ at their team members on the court/field.