Jack Black surprises Jonas Brothers audience with song from ‘Super Mario Bros. Movie’

He was feeling just peachy.

Jack Black surprised Jonas Brothers fans Saturday, when the “School of Rock” alum appeared during the trio’s performance at Brooklyn’s Barclays Center to perform his song, “Peaches,” from “The Super Mario Bros. Movie.”

Black, 54, appeared during the show’s intermission wearing a shimmering green suit and a red mohawk wig — resembling his character in the film, Bowser — and dedicated the song to the Jonas Brothers and his “one true love.”

“This song goes out to my one and only true love, Princess Peach,” Black said as he rose from underneath the stage. “And to my good friends, the Jonas Brothers.”

“The one… The only… @jackblack 🔥 #THETOUR,” the Jonas Brothers wrote on their official Instagram account . 

The “Holiday” star’s performance came only days before the song was nominated for a Golden Globe for Best Original Song from a Motion Picture. 

The Post has reached out to Black’s reps for comment.

Several fans went wild at the “Nacho Libre” alum’s appearance.

“THE WAY I WOULD HAVE PASSED AWAY,” one fan screeched.

“OMG I would die to see that,” a second person said.

One unlucky fan admitted that they “can’t believe I was in line getting pizza and missed this.”

Black’s number, which initially was not slated to be included in the Nintendo film, topped the Billboard Hot 100 chart at #56.

The song is also eligible to be nominated at the upcoming Academy Awards.

Saturday’s show marked the second-to-last stop on the Jonas Brothers’ current itinerary, until “The Tour” picks up again in New Zealand in February 2024.

Fans of the boy band were elated to learn Nick, Kevin and Joe Jonas — the last of whom is currently in a legal battle with ex-wife Sophie Turner — will be launching a 20th anniversary tour in 2025.

“[From] two nights at Yankee Stadium, we have since played 61-or-something shows,” Nick, 31, said Sunday during their final show according to Us Weekly. “We’ve reached the end, but we left you all a card on your seats, I don’t know if you got those when you got in.” 

Joe, 34, then asked his younger brother what the note said.

“OK, so in 2025, it’ll be the 20-year anniversary of this band,” continued Nick. “And that card was your formal invite [because] we’re gonna do this thing again.”

“The Tour” began on Aug. 12 at Yankees Stadium and covers the band’s five-album discography over the course of a three-hour show.

According to The Post’s Chuck Arnold, the JoBros tour doesn’t come “with much spectacle” save for the obvious (and one might say obligatory) pyrotechnics for their hit “Burnin’ Up.”

“No matter what your favorite Jonas Brothers track is, you’re going to hear it at some point during the night,” wrote Arnold.

The “Super Mario Bros.” film is currently available to stream with a Netflix subscription or to rent on Amazon Prime.