The Gers suffered a stunning collapse in the final 20 minutes of the Scottish Championship game at the Falkirk Stadium.
The Glasgow giants took the lead as early as the seventh minute when Kenny Miller found the target.
Rangers went 2-0 up just two minutes later through Barrie McKay, and it appeared as though the Gers were going to win by a very big margin.
However, Warburton’s side collapsed in the final 20 minutes of the game to lose 3-2, as Blair Alston, Myles Hippolyte and Bob McHugh found the target for the home side.
Celtic manager Deila was at the Falkirk Stadium, probably doing research on their Scottish Cup semi-final opponents Rangers.
Warburton has made it clear that he is not fussed about what the Norwegian thought of his side’s performance.
"I don’t mind what Ronny thought,” the Englishman told The Glasgow Evening Times when asked what he thought Deila made of the result. “I hope he enjoyed the game."
Celtic are at the top of the Scottish Premiership table at the moment, while Rangers lead the Scottish Championship standings.