Thin Lizzy are about to be down one guitarist, but fear not - they've already got a high caliber replacement lined up!

Guns N' Roses' guitarist Richard Fortus will take over from Vivian Campbell after Lizzy play Slane, along with Kings of Leon, on May 28. Fortus will be with the band when they play the High Voltage Festival, while Campbell will return to Def Leppard duties.

Fortus has already begun getting into the swing of things - he took to the stage with the the rest of Thin Lizzy at their Chicago show on Friday - the final gig of their US tour. Check out footage from the show below.

Campbell will perform with the band at Slane in May, but will then bid Ricky Warwick & Co. a fond farewell. He said on his Facebook page: "Well, that was it: my last U.S. show with Lizzy - and it was a great one to end on. New guitarist Richard Fortus came and played a couple of songs. I have one final gig with them in Ireland, and the very next day we start Def Lep rehearsals."

That may not be the end of Campbell's involvement with the band though. Speaking to Gibson.com, the guitarist said "[Lizzy] have very kindly offered me the opportunity to come back when my schedule with Def Leppard opens up, and you can bet that I'll be there in a heartbeat!"