British rocker Paul Mario Day, best known as the original vocalist of Iron Maiden, has died at age 69.

The heavy metal musician died peacefully at his home in Australia Tuesday, his family revealed.

While an official cause of death is unknown at this time, the rocker had been battling cancer in recent years, Parade reports.

Day joined Iron Maiden as the group’s first vocalist in December 1975 at just 19 years old after being recruited by bassist Steve Harris.

However, Day’s tenure with the iconic band lasted just 10 months and saw him leave following claims he lacked both energy and charisma.

“When I sang in Iron Maiden, it was a new pub band and nobody wanted to see or hear them,” Day mentioned in 2019 regarding his period with the group. “We were all nobodies all trying to make the best music we could and fighting for an audience.”

Day performed at Iron Maiden’s first gig in May 1976 in London.

Shortly after, he was replaced by Dennis Wilcock — another short-lived member of the group who exited the following year.

Wilcock’s position was eventually filled by Paul Di’Anno, who performed on the band’s first two albums before the enduring vocalist Bruce Dickinson stepped in permanently.

After Day’s departure, the rocker later asserted that he co-wrote the track “Strange World” — from the group’s self-titled 1980 debut album — but unfortunately did not receive any credit.

“Back then we were all pulling for the same side and it still hurts to think the first-ever song I ever composed was on a big-selling album and nobody knows it was me,” he said in 2019.

Still, the drama had blown over by that time as Day declared that the issue was “finished with.”

Following his swift exit from Iron Maiden, the rocker formed the band More in 1980, with the group releasing its debut album “Warhead” the following year.

Following Day’s death, his former More bandmates paid tribute to him in a post on social media.

“We are deeply saddened to learn of the passing of the great More vocalist Paul Mario Day,” his former band More wrote on Facebook.

“Paul was a huge part of the NWOBHM from his time in an early version of Iron Maiden, and of course his fantastic performance on the ‘Warhead’ album.”

“He was a well-loved figure in British rock music and played many memorable shows, not least the legendary 1981 Monsters of Rock show at Castle Donington with AC/DC, Whitesnake/David Coverdale, as well as tours with Iron Maiden, Def Leppard and many other legendary artists,” they added.

After moving on from More, Day fronted the band Wildfire from 1983 to 1984.

His most commercially successful stint was in 1985 when he joined the reformed version of glam rock legends Sweet.

The gig saw him collaborate with guitarist Andy Scott and drummer Mick Tucker, who have paid tribute to Day following news of his death.

“In 1985 Mick Tucker and myself put together the first new line-up of Sweet after the hiatus of the original band,” Scott wrote on Facebook. “We needed a singer and when Paul arrived for the audition we looked no further. 

Day had relocated to Australia in the 1980s, where he remained until his death.

“My deepest condolences to his wife Cecily and family and friends,” Scott added. “A sad day for all Sweet fans.”