Pugnacious MSNBC host and political commentator Chris Matthews stunned viewers on Monday, announcing his retirement from his nightly “Hardball” show — effective immediately.

How immediate? Matthews didn’t even bother to finish the show.

“I’m retiring,” he said in the opening moments of Monday’s program. “This is my last Hardball on MSNBC.”

He will be replaced at 7 p.m. by a rotating group of hosts.

Matthews, 74, said he and MSNBC had mutually agreed to part ways. In recent weeks, Matthews had come under fire for a series of controversial statements he made about Bernie Sanders and African-American lawmakers, and sexist comments he had made to female journalists and coworkers.

Just last Monday, Matthews apologized to Sanders for comparing his rise in the 2020 campaign to the German invasion of France.

“I’m sorry for comparing anything from that tragic era in which so many suffered, especially the Jewish people, to an electoral result of which you were the well-deserved winner,” Matthews said during his on-air mea culpa.

On Monday, Matthews said it was time to leave his show in younger hands.

“After conversations with MSNBC, I’ve decided tonight will be my last ‘Hardball.’ Let me tell you why: The younger generations out there are ready to take the reins. We see them in politics, and the media and fighting for their causes. They are improving the workplace. We’re talking here about better standards than we grew up with, fair standards. A lot of it has to do with how we talk to each other, compliments on a woman’s appearance that some men, including me, might have once incorrectly thought were OK – were never OK. Not then and certainly not today, and for making such comments in the past, I’m sorry.”

In less than two minutes, Matthew signed off and handed over the hour to a visibly shaken MSNBC anchor Steve Kornacki.

“Um, that was a lot to take in just now, I’m sure,” Kornacki said. “And I’m sure you’re still absorbing that, and I am too. Chris Matthews is a giant. He’s a legend. It’s been an honor for me to work with him, to sit in here on occasion. And I know how much you meant to him. I think you’re going to miss him. And I know I’m going to.”

Kornacki went on to say there would be “no bells and whistles” on Monday’s program before acknowledging that “we do have to fill this hour.”

Matthews was due to retire in the near future with recent events playing a factor in the timing of the move, an MSNBC spokesperson said.

Just three days ago, Matthews was the subject of a GQ.com column in which the author, Laura Bassett, wrote that Matthews behaved in a “gross” and “inappropriate” manner when she was a guest on his show. Bassett also cited Matthews’ aggressive questioning of Democratic presidential candidate Sen. Elizabeth Warren of Massachusetts following NBC’s primary debate on Feb. 19 as an example of his sexism. During that interview, Matthews repeatedly pressed Warren about her criticism of Michael Bloomberg and his company’s handling of allegations of sexual harassment and gender-based discrimination.

“His tendency to objectify women in his orbit has bled into his treatment of female politicians and candidates,” Bassett wrote.

NBC News has acknowledged that there has been one financial settlement paid to a former female employee who complained about Matthews’ behavior. The host reportedly received a stern reprimand over the matter.

The controversial Matthews was one of the longest-tenured voices at MSNBC. But he generated a great deal of criticism along the way. Shortly after announcing his resignation, the watchdog group Media Matters issued a statement calling his departure “long overdue.”

“He has a decades-long history of misogyny — on and off the air — and even openly bragged about whether women measured up to his ‘Chris Matthews test’ of women’s attractiveness,” the statement continued. “He spoke derisively of female politicians, complaining about their voices and diminishing their accomplishments. He had a particular fixation on whether powerful women were ‘castrating’ their male counterparts. …”