Rangers' recent run of good form came to a crashing halt as they were thrashed 4-1 away to Hearts.
The loss puts them a staggering 25 points behind leaders and rivals Celtic, who beat Aberdeen 1-0.
Rangers were in the game at 1-1 with loanee Emerson Hyndman scoring the goal, but they fell apart in the second half and the margin of victory for Hearts could easily have been higher.
Former Celtic striker and pundit Chris Sutton blasted their performance, commenting that their midfield was too lightweight.
He told BT Sport's post-game coverage: "They got torn to shreds in the middle of the park. Young lads, with no experience. Do they have a physical presence up top? Hearts outsmarted them. I'm really pleased for Ian Cathro tonight."
Chris Sutton - Glasgow Celtic
Sutton said he feels Rangers got it wrong again in the transfer window, with loan deals for the likes of Hyndman and Jon Toral essentially being pointless.
He said: "Thats Rangers Football Club, it's about winning games. I question about what happened in Janaury.
"These lads are going to go back to their clubs, essentially they are not developing their own. They were like an academy team second half, no plan B.
Commenting on former Brentford boss Warburton's future, Sutton added: "He'll last until the end of the season but then who knows."
Rangers manager Mark Warburton
Celtic have enjoyed huge success after changing their manager in the summer, but before Rangers consider doing the same, they should reflect that Warburton has been operating on a shoestring budget.
He has failed to get the squad balance right, aiming for young raw talent or veterans, rather than established professionals in the midst of their careers, but financially he has one hand tied behind his back, which makes signing the difference makers he needs highly difficult.