Prime Minister Benjamin Netanyahu and Blue and White Party leader Benny Gantz have been campaigning against each other for 14 months without what political strategists call a “game changer.”Netanyahu delivered what could have finally been that game changer on Tuesday night when he challenged Gantz to a debate. But Gantz deliberately dropped the ball. Why could debating Netanyahu have been a game changer for Gantz?Because he would have finally been on a level playing field with Netanyahu, playing his own game. Everyone knows Netanyahu speaks well, so he had nothing to gain from a debate, and therefore he avoided debates for more than 20 years.Gantz, by contrast, had everything to gain. He could have countered the image given to him by Netanyahu as an empty general controlled by public relations advisers, by showing that he is an articulate, deep thinker with a well-thought-out agenda on key issues.After a year of people saying that Gantz was nothing more than “anyone except Bibi,” Gantz, whose party actually has a lengthy platform, could have used the debate to familiarize the public with what he stands for, had he called Netanyahu’s bluff.Asked why Gantz rejected the debate challenge after he himself called for a debate in all three elections, including just this past Saturday night, Gantz’s advisers answered that he did not want to play into Netanyahu’s political spin.So the timing of Netanyahu’s challenge the same day that the date of his trial was announced was annoying for Gantz. That is understandable, but the agendas of elections are constantly changing.Two prime-time nightly newscasts led their headlines Wednesday night with reports that Attorney-General Avichai Mandelblit would soon probe Gantz’s bankrupt company The Fifth Dimension. Now it is Gantz who needs to change the agenda, but he lost the opportunity to shift it to a debate, because he ruled it out so firmly five hours earlier.Netanyahu will use The Fifth Dimension probe to suggest that if he is corrupt, then all politicians are. A debate would have been a good place to explain to the public that there is a difference between vetting a case and three criminal indictments on seven charges.It is too late now for this game changer to come back to Gantz. If another one comes his way by March 2, it will be up to him to decide whether or not to catch it.