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Donald Trump’s rivals are seizing on his decision to skip Thursday’s Fox News/Google debate, with Ted Cruz in particular using the boycott to challenge his closest rival’s readiness for office.

“If you're afraid to have anyone ask a question, that does not bode well for what kind of commander-in-chief you'd make,” the Texas senator told Fox News’ “Hannity,” on the heels of Trump’s decision.

Other candidates also suggested Trump’s absence might help give the rest of those on stage a better chance to be heard.

“It’ll give us more time to talk,” New Jersey Gov. Chris Christie told Fox News. “And that’ll be good for me and good for the other people on the stage.”

Christie, too, ripped Trump for his decision, saying: “You gotta show up.”

Former Florida Gov. Jeb Bush made a similar comment on Twitter, shortly before Trump formally backed out of the debate:

Trump’s decision had escalated out of a feud between him and co-moderator Megyn Kelly.

Trump, for his part, doubled down on his decision Wednesday, taking to Twitter to criticize both Kelly and Fox News. Trump campaign manager Corey Lewandowski told MSNBC’s “Morning Joe” that the boycott had “nothing to do with Megyn Kelly.”

But a half-hour later, Trump again went after Kelly on Twitter, calling her a “lightweight reporter.”

Trump also has cited press statements by Fox News, pertaining to his feud with Kelly, that apparently contributed to his decision not to participate in Thursday’s debate.

The Fox News/Google debate is set for this Thursday in Des Moines, Iowa, and would mark the first GOP presidential primary debate that Trump has not attended.

Cruz, who is battling to make up ground against Trump in the Iowa polls ahead of next week’s caucuses, had some of the toughest statements on Trump’s decision.

“If you're afraid of Megyn Kelly, then you're going to be afraid of Hillary Clinton and you're going to be afraid of Vladimir Putin,” Cruz said.

Addressing the matter on “The Kelly File,” Kelly said: “I’ll be there. … The debate will go on with or without Mr. Trump.”

Trump’s campaign said in a statement that instead of doing the debate, Trump “will instead host an event in Iowa to raise money for the Veterans and Wounded Warriors.”

Whether Trump’s decision helps or hurts his campaign in Iowa and beyond remains to be seen.

READ THE FOX NEWS STATEMENT ON TRUMP DECLINING TO PARTICIPATE IN FOX NEWS/GOOGLE DEBATE.

Despite his complaints, he had qualified as one of the eight candidates in the prime-time event Thursday. Fox News announced the candidate lineup for that debate earlier Tuesday evening, and the qualifying participants were:

Trump; Cruz; Florida Sen. Marco Rubio; retired neurosurgeon Ben Carson; Bush; Christie; Ohio Gov. John Kasich; and Kentucky Sen. Rand Paul.

The participants qualifying for the earlier, 7 p.m. ET debate were:

Former HP CEO Carly Fiorina; former Arkansas Gov. Mike Huckabee; former Pennsylvania Sen. Rick Santorum; and former Virginia Gov. Jim Gilmore.

Meanwhile, Fox News Chairman Roger Ailes has defended Megyn Kelly amid the criticism from Trump. He issued a statement earlier to The Washington Post saying, “Megyn Kelly is an excellent journalist, and the entire network stands behind her. She will absolutely be on the debate stage on Thursday night."

Fox News also issued a statement after Trump’s decision saying Lewandowski had threatened to ramp up the attacks.

“In a call on Saturday with a FOX News executive, Lewandowski stated that Megyn had a ‘rough couple of days after that last debate’ and he ‘would hate to have her go through that again,’” a Fox News statement said late Tuesday.

“Lewandowski was warned not to level any more threats, but he continued to do so. We can’t give in to terrorizations toward any of our employees,” the statement added.

The Fox News/Google debate in Des Moines this Thursday will be the candidates’ last before next week’s Iowa caucuses – which kicks off the Republican presidential nominating process.

The debate will be moderated by Fox News anchors Bret Baier, Chris Wallace and Kelly.