Axl Rose, back with Guns N' Roses, to Front AC/DC

Axl Rose fired up a reunited Guns N' Roses at the Coachella festival on Saturday as he was announced as the new frontman of an even more veteran hard rock group -- AC/DC.

In one of rock's most long discussed reunions, Rose performed on the festival stage in the California desert with guitarist Slash, who until this month had not joined his former bandmate and on-off nemesis for more than two decades.

Guns N' Roses added a fresh surprise as Angus Young, the lead guitarist of AC/DC, suddenly appeared on stage late in the set, hours after the Australian rockers named Rose as their at least temporary new singer.

In a preview of the new AC/DC, Rose brought out his classic intense scream for the Australians' "Whole Lotta Rosie" as Young pranced on stage in his trademark school uniform and let loose with rapid-fire guitar in coordination with Slash.

Yet Rose on his day of triumph projected an awkward image: a recent injury confined him to a chair, with his left leg in a cast. The singer famous for his emotional intensity and races across stage fidgeted in a sort of sedentary, agitated dancing.

AC/DC broke off a North American tour last month after saying that singer Brian Johnson, 68, risked permanent loss of hearing if he kept performing with the notoriously loud band.

The band said Rose would front AC/DC on a 12-show European leg starting on May 7 in Lisbon.

Rose will then return to North America for the arena tour of the reformed Guns N' Roses, with the 10 postponed AC/DC dates in the United States to be rescheduled later.

Rose, like Johnson, can bring out a punishing grittiness on high notes, but the Guns N' Roses frontman enjoys a much more versatile vocal range.

AC/DC kept open whether Rose would stay permanently. The band had planned shows only until June at the end of a marathon global tour for its 2014 album "Rock or Bust."

But the band made clear that Johnson was out, issuing a statement thanking him "for his contributions and dedication to the band throughout the years."

"We wish him all the best with his hearing issues and future ventures. As much as we want this tour to end as it started, we understand, respect and support Brian's decision to stop touring and save his hearing," it said.

Johnson, however, has been quiet in public and has reportedly voiced dismay at his swift exit. U.S. comedian and radio host Jim Breuer said he spoke to Johnson, who felt "kicked to the curb" by his bandmates and did not believe his hearing problems were as serious as described by the group.

Johnson was not an original member of AC/DC, joining after singer Bon Scott died in 1980 after a night of heavy drinking.

The loss of Johnson is the latest major change for AC/DC. Malcolm Young, the rhythm guitarist and brother of Angus, retired before "Rock or Bust" as he suffers dementia.

Drummer Phil Rudd was pushed out after he was arrested on charges of ordering a murder in New Zealand, where he lives.

Guns N' Roses became global sensations with 1987's "Appetite For Destruction," which remains the best-selling debut album ever.

But the rough living described in the songs was not far from reality and the band suffered frequent friction, with the classic lineup calling it quits after a 1993 show in Buenos Aires.

A reunion had long been thought impossible, with Rose a few years ago calling Slash "a cancer" and refusing to join him at the band's Rock and Roll Hall of Fame induction.

But Slash and Rose -- who are expected to earn millions of dollars for the reunion -- briefly locked arms as they bid farewell to fans after their encore, which culminated in flames on stage and fireworks above.

Guns N' Roses played their best-known hits, from deviant "Appetite for Destruction" anthems to the mega-ballad "November Rain," but also "Chinese Democracy," with Slash performing the 1998 title track of the infamously delayed album that came out after his departure.

While the reunion was announced for Coachella, the band played a surprise show on April 1 at the Troubadour, a small Los Angeles club where the group was discovered, and then two shows at a new arena in Las Vegas.

In a noticeable break from the past, the band opened its Coachella set on time.