By mid-1973, the bloom was off the rose for Deep Purple. Internal issues had risen to the top and long-standing lead singer Ian Gillan opted to leave the band. At the same time, bassist Roger Glover was told his services were no longer needed, by direct order of guitarist Ritchie Blackmore. The Deep Purple lineup known as Mark II, was no more.

The band had been at it since 1968, but once Gillan joined up in 1970, things really took off. The early '70s were defined by such landmark LPs as In Rock, Fireball and Machine Head, which spawned their massive worldwide hit "Smoke on the Water." But egos and other factors got in the way, and the band were quickly falling apart.

"There was a very strong suggestion from my part to call it a day," the late keyboardist Jon Lord told Classic Rock magazine in 2002.

Drummer Ian Paice was unsure what direction, if any, the band should take, but Lord had his own thoughts. "I think had it not continued as Purple, Ritchie would have grabbed one or the both of us and done something else. He'd already experimented with Phil Lynott and Paicey as a trio."

Gillan wanted out and actually submitted a resignation letter to the band while on tour promoting their 1973 album, Who Do We Think We Are.

"The letter from Ian Gillan was a dreadful shame," Lord continued. "He felt something wasn't right, and I personally would have been happier if he'd stayed and fought from within. It was really just beginning to take off in the States in a big way, which is what we'd been working so hard for. Maybe if we'd taken some time off it might have been a different story." Gillan's mind was made up, however, and following a tour-ending June 29, 1973 at Osaka, Japan, he was gone.

The band already had someone in mind to take Glover's place on bass. Lord and Paice had been highly impressed with Glenn Hughes upon seeing his band Trapeze, but finding a replacement for their stellar vocalist would prove another matter. "We got boxes and boxes of tapes and didn't hear anything we liked," Lord said.

Ritchie Blackmore wanted to try and nab Paul Rodgers, but the others didn't agree. Eventually they found David Coverdale, whose vocal style was similar enough to Rodgers to please Blackmore.

Unfortunately, Deep Purple were less impressed with another aspect of Coverdale on first meeting: his fashion sense.

"He was wearing disastrous flares — loon pants, I think they used to call them — it was a dreadful sight," Lord said. "And he had this wandering eye, which we had fixed quite quickly, and he grew his hair, because he had this strange bouffant style that didn't suit him. He also had this slightly transparent caterpillar on his top lip. I said, 'There's only one fucking mustache in this band, and it's mine!'"

The Mark III lineup took on a life of its own with Burn, but wouldn't last very long. Soon, Blackmore himself exited the band, too.

Meet the New Boss: Rock's Replacement Singers

Some bands soar to their greatest heights after an original frontman leaves. Others must deal with the past's towering expectations.

Jon Lord and Ian Paice Were in One of Rock’s Forgotten Supergroups

More From Ultimate Classic Rock