When Fall Out Boy announced their reformation earlier this year, the group told fans via an article in Billboard Magazine to prepare themselves for some untypical collaborations.

While not many names have dropped with respect to the potential guests that will be featured on the group's upcoming record, Fall Out Boy vocalist Patrick Stump tweeted the above photo of himself sitting with the legendary Elton John in the recording studio. Stump offered nothing other than the hashtags "#saverockandroll" and "#sireltonjohn," so John's exact involvement in the group's new material remains to be seen. Needless to say, the band is delivering on their promise of some "left-field" guests.

John's collaboration with Fall Out Boy isn't a complete random encounter however as the band has a history of collaborations with their musical heroes. On their 2008 album 'Folie A Deux', Elvis Costello contributed vocals while 2007's 'Infinity On High' saw the group welcome a contribution from superstar rapper Jay Z.

Fall Out Boy's new record 'Save Rock n Roll' is scheduled for release in April.

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