WWE are believed to have finally persuaded Sting to put pen to paper on a contract with the company.
The WCW legend has famously resisted Vince McMahon's advances to join his roster in the past.
He most recently worked in Total Non-Stop Action Wrestling [TNA], but his deal with them expired last year and he has since been involved in discussions to sign for the WWE, with an agreement now apparently reached.
Dave Meltzer wrote in the Wrestling Observer Newsletter: "Sting has signed his deal with WWE. Not sure of the details regarding what role he will play but he is scheduled to be on television at some point, but not right away... the deal described to me as being close for a while, but now it's signed.
"Sting's assumption was he would work with Undertaker, which many expected. With Undertaker losing, and his future being in question, that would be up in the air."
Reports claim that The Undertaker will not wrestle again following his shock loss to Brock Lesnar at WrestleMania XXX on April 6, which ended his 21-match undefeated streak on the Grandest Stage.