When Trump’s name came up during a word association game on MSNBC’s “Morning Joe,” Bush immediately responded “loser.” The former Florida Governor had more to say about Trump, going after the rest of the GOP for not attacking the real estate mogul.

“The guy’s just a real-estate guy,” Bush said. “He’s gone bankrupt four times. He’s a successful man, but he’s not perfect by any stretch of the imagination. So why not confront him and challenge him?”

“Jeb is an interesting duck,” Trump said. “Here’s the story on Jeb: He’s a stiff who you wouldn’t hire in private enterprise, OK? This is a stiff. This is a guy that if he came looking for a job, you’d say, ‘No thank you.’ And that’s the way it is.”

Trump, the Republican front-runner, has been insulting Bush, the establishment darling trying to regain his place in the polls, since the beginning of the campaign, dubbing him a “low-energy” candidate. Bush attempted to take the high road, telling Trump at a December Republican debate: “You’re not going to be able to insult your way to the presidency.”

Bush seems to have since given up, taking charge in the effort to take Trump head on—even calling the practice “therapy.” He later clapped back at Trump on Twitter, repeating the insult.

.@realDonaldTrump, you aren’t just a loser, you are a liar and a whiner. John McCain is a hero. Over and out.

— Jeb Bush (@JebBush) February 8, 2016

This article was originally published on Time.com.