Republican presidential candidates Jeb Bush (L) and Ted Cruz (R) talk during a commercial break in the CBS News Republican Presidential Debate in Greenville, South Carolina, Feb. 13, 2016. Jim Watson/AFP/Getty Images

For a moment the GOP debate in South Carolina Saturday sounded less like a forum for U.S. presidential hopefuls and more like a school playground. Donald Trump, retaliating for a string of insults from Jeb Bush, accused Bush of saying he'd remove his pants and flash his rear.

Trump was right. In a Feb. 6 interview with the Boston Globe, Bush bemoaned his campaign's failure to capture the media's attention. "I could drop my pants," the former Florida governor said, sitting on his campaign bus. "Moon the whole crowd. Everybody would be aghast, except the press guys would never notice."

Caption:Republican presidential candidate Jeb Bush speaks during the CBS News Republican Presidential Debate in Greenville, South Carolina, Feb. 13, 2016. Jim Watson/AFP/Getty Images

Trump revived the line Saturday after Bush called the real estate billionaire "weak" for his disparaging remarks on women, Mexican immigrants and a disabled reporter.

Trump and Bush were among six Republican presidential candidates at the debate, hosted by CBS News. Florida Sen. Marco Rubio, Texas Sen. Ted Cruz, Ohio Gov. John Kasich and retired neurosurgeon Ben Carson also took the stage Saturday.

Bush's "moon" comments to the Boston Globe arrived as hints of desperation and exasperation loomed over his campaign. He was heading into the Feb. 9 primary in New Hampshire, where he went on to win just 11 percent of the vote. Trump rebounded to first place, with over 35 percent of votes, after landing in second place behind Cruz in the Feb. 1 Iowa primary.

Republican and Democratic candidates face their next primary in South Carolina next week. Trump is currently crushing the GOP field in the Palmetto State with more than double the support for Cruz, his closest competitor, according to a Feb. 12 poll by the South Carolina House Republican Caucus.

Trump secured 34.5 percent support, followed by Cruz with 15.5 percent, Bush with 13 percent and Rubio with 12.5 percent. The poll surveyed 1,200 likely Republican primary voters from Feb. 11 to 12, The Hill reported.

The Feb. 20 primary in South Carolina is expected to be a crucial night for Trump. If he can land a strong lead in the state, his march to the GOP nomination might be hard to stop, The Hill noted.