Chicago have replaced singer and bassist Jason Scheff, who took over for Peter Cetera before 1986's Chicago 18. The band confirmed today that Jeff Coffey, who "has been touring with Chicago in recent months," will take over.

Scheff had been on a leave of absence, citing "family health reasons" back in May. At that point, he said he didn't intend to leave Chicago. "We're in the middle of a pretty great run," Scheff said, "and I'm having the time of my life."

He arrived at the tail-end of Chicago's hitmaking period with producer David Foster, who had previously worked with Chicago on both Chicago 16 and 17. But Scheff's debut single, a reworked version of Chicago's classic song "25 or 6 to 4," flopped – reaching only No. 48.

Scheff and Chicago quickly rebounded with a pair of smash ballads, 1986's "Will You Still Love Me?" (which went to No. 3) and 1987's "If She Would Have Been Faithful" (a No. 17 hit). "What Kind of Man Would I Be?" followed in 1989 and reached No. 5.

"We are so grateful to Jason for the enormous contribution he has made to Chicago over the last 30-plus years," the band said. "Everyone wishes him and his family all the best as he continues his musical journey."

Scheff had already announced a role as judge on American Supergroup, a new music competition that premiered on MTV Classic earlier this month. According to Coffey's website, his career includes turns performing and touring with Hootie and the Blowfish, Edwin McCain, Sixpence None the Richer and Vertical Horizon.

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