Stone made an appearance on the May 5, 2005 episode of WWE SmackDown under the ring name Rob Eckos, where he lost to Matt Morgan. On January 2, 2006, Eckos made another appearance for World Wrestling Entertainment, when he was attacked in a skit by Edge, who was doing a mock impersonation of Ric Flair during WWE Raw.
On March 11, 2019, it was reported that Eckos had signed with WWE and would be reporting to the Performance Center. On March 21, he debuted at an NXT house show as a heel manager named Robert Strauss, managing Rinku Singh and Saurav Gurjar. In his promo, Strauss went on to say, "he isn't a manager he's a brand." Shortly after his stable of clients grew to include Riddick Moss. He started appearing at house shows as the manager of The Outliers, a tag team consisting of Moss and Dan Matha. On July 17 2019, his ring name was changed to Robert Stone.
On January 8th, 2020, he made his NXT television debut introducing Chelsea Green as his new client. On the May 27, 2020 episode of NXT, after Chelsea Green and Charlotte Flair defeated Rhea Ripley and Io Shirai, Green fired Stone. Over the next few weeks, Stone would appear on NXT with tattered clothes and unkempt hair after being fired by Green as he tried to recruit Rhea Ripley as his new client, to no avail. On the June 17 episode of NXT, Stone would officially recruit Aliyah after he helped her defeat Xia Li. Stone and Aliyah would feud with Ripley as Ripley defeated Aliyah on the June 24 episode of NXT. The following week on NXT The Great American Bash, Stone competed in his debut match alongside Aliyah against Ripley with the stipulation that if Ripley lost then she would join the Robert Stone Brand, but they were defeated. On the July 22 episode of NXT, Stone officially recruited Mercedes Martinez into the Robert Stone Brand after she attacked Shotzi Blackheart.
In 2021, Stone's name would be shortened to Mr. Stone and he would begin to manage Von Wagner alongside Sofia Cromwell until July 22, 2022, when Cromwell made her main roster debut. In August 2023, Von Wagner turned face when he began opening up about his childhood struggles to Stone and subsequently began feuding with Bron Breakker, thus turning Stone face as well. In April 2024, Wagner was released from WWE, effectively ending their partnership. On the May 21 episode of NXT, Stone began managing Dante Chen, who defeated Lexis King later that night.