Rangers face Greenock Morton in the Scottish Cup on Sunday, live on Sky Sports, with confusion over who will take charge of the team.
The Gers announced on Friday evening that they had accepted the resignations of Warburton, assistant manager David Weir and head of recruitment Frank McParland.
Sky sources understand Warburton, Weir and McParland categorically deny resigning from Rangers.
Rangers say U20s coach Graeme Murty has been placed interim control of first-team affairs and will be in the dugout at Ibrox for the visit of Morton.
Defender Danny Wilson could be handed his first start since New Year's Eve having been an unused substitute for last Saturday's 1-1 draw with Ross County.
Forward Michael O'Halloran returns from suspension but midfielders Jordan Rossiter (calf) and Niko Kranjcar (knee) remain out.
Morton will be without striker Gary Oliver who suffered medial ligament damage in the 3-0 at Queen of the South last weekend.
The Scottish Championship side, who have lost just one of their last nine games, will take heart from the 2-2 draw they secured at Ibrox last season.
They currently sit third in the Championship, nine points adrift of leaders Hibernian, and manager Jim Duffy says they will travel to Govan in good heart.
He said: "Our job will be to stay in the game and be difficult to beat.
"If Rangers get nervous, and the fans frustrated, then you never know. But we have to be good enough to take advantage of those situations."