Hillary Clinton and Bernie Sanders have thrown pleasantries out the window.

The election season's ninth Democratic presidential debate took place in Brooklyn on Thursday night, in a state with 291 delegates at stake next week. Clinton needs a win to cool Sanders' surge; counting the Wyoming primary, Sanders has won seven consecutive contests dating back to March 22.

Sanders needs most, if not all, New York's delegates to keep pace with Clinton. He trails by the former Secretary of State by 658 delegates three months from the Democratic National Convention in Philadelphia, one Sanders hopes to contest.

Thursday's CNN debate was a contentious affair. Months of campaign stops and repeated policy stances are beginning to wear on the candidates, and it showed throughout the night. Sanders' wry sense of humor clashed with Clinton's pragmatism.

Clinton ducked questions about Wall Street speeches. Sanders mixed sarcasm with substance, losing a few votes among those opposing his views on Israel and an ongoing lawsuit of gun manufacturers by Sandy Hook parents.

Neither can afford to lose Tuesday primary. The Brooklyn debate, the final scheduled Democratic debate, proved as much.

Wall Street Speeches and Tax Returns

CNN moderators tagged Clinton over her refusal to release Goldman Sachs speech transcripts. Dana Bash repeatedly asked the former Clinton about her unwillingness to do so, reiterating that Democratic voters want transparency.

Clinton redirected Bash's question to candidates' tax returns.

"There is a long-standing expectation that everybody running release their tax returns," Clinton said. "I've released 30 years of tax returns. And I think every candidate, including Senator Sanders and Donald Trump, should do the same."

Sanders said he would release 2014 tax returns on Friday and mocked Clinton's assertion that she fought big banks while serving as New York senator.

"Senator Clinton called them out, oh my goodness. They must have been really crushed by this," Sanders said to applause. "Was that before or after you received huge sums of money by giving speaking engagements behind closed doors? They must've been really upset."

In his own words, Sanders said his returns won't be exciting because he didn't give Wall Street speeches and remains "one of the poorer members" of the Senate.

Sanders Calls Violence in Israel 'Disproportionate'

Asked about the 2014 Israel-Gaza war that left thousands dead on the Gaza Strip, Sanders called Israel's response "disproportionate" and led to "the unnecessary loss of innocent life."

"The question is not does Israel have a right to respond, nor does Israel have a right to go after terrorist and destroy terrorism. That's not the debate. Was their response disproportionate?" Sanders asked. "I believe it was."

Sanders said he is "100 percent pro-Israel" but believes Palestinian people should be treated with respect and dignity, comments that may not sit well with pro-Israel advocates.

Clinton didn't press Sanders for a direct answer, instead referencing to peace talks with Middle Eastern leaders like Israel Prime Minister Benjamin Netanyahu and Palestinian Authority President Mahmoud Abbas.

"I have been there with Israeli officials going back more than 25 years that they do not seek this kind of attacks," Clinton said. "They do not invite the rockets raining down on their towns and villages."

Memorable Quotes

"We are going to have to say that Netanyahu is not right all the time" - Sanders, on the Israeli prime minister.

"Describing the problem is a lot easier than trying to solve it," - Clinton defending her role in the Israel-Palestinian conflict as secretary of state.

"If you're both screaming at each other, the viewers won't be able to hear either of you," - CNN moderator Wolf Blitzer.

"I've been called a lot of things, and that was a first," - Clinton, after Sanders called her "unqualified."

"We've had eight debates before, this is our ninth. We've not had one question about a woman's right to make her own decisions about reproductive health care, not one question," - Clinton.

"Public colleges and universities tuition fee? Damn right," - Sanders.

"We've heard a lot from Senator Sanders about the greed and recklessness of Wall Street, and I agree. We've got to hold Wall Street accountable. We'll, what about the greed and recklessness of gun manufacturers and dealers in America?" - Clinton, on Sanders' gun policy record in Vermont.

"I am sure a lot of people are very surprised to learn that you supported raising the minimum wage to $15 bucks an hour," - Sanders, citing Clinton's initial disapproval of the measure.