Barry Ferguson has told The Daily Record that Celtic's Champions League defeat in midweek is a glaring reminder as to how much work Rangers need to do in order to get back into Europe's elite competition.
Paris Saint-Germain, armed with the likes of Neymar and Kylian Mbappe, put Celtic to the sword as the big-spending French outfit thumped the Hoops 5-0 at Parkhead this week.
As a former Rangers man, Ferguson admits that he enjoyed watching such a "phenomenal display" against the Bhoys, but believes that the in-form Gers among others should be worried that such a heavy defeat could have a knock-on effect for them.
This time last year, Brendan Rodgers's side were left reeling from a 7-0 defeat away to Barcelona in their Champions League opener, but the Bhoys looked galvanised - domestically, at least - by such a thumping and didn't lose a single game for the rest of the season in any Scottish competition.
And the Ibrox legend wouldn't be surprised to see Rodgers draw the same response from his troops again this time around, spelling bad news for other Scottish sides.
“Hands up, I enjoyed watching it myself because it really was a phenomenal display of football from the French side,” he told the Daily Record.
“But the gap between the strongest team in Scotland and the biggest clubs in Europe shouldn’t really be a laughing matter for anyone right now.
“In fact, it should come as a sharp reminder to everyone at Rangers of how much work is still to be done if my old club are to make it back to the biggest stage.
“And it should also serve as a warning to them because it was only 12 months ago that Celtic suffered a similarly heavy-handed slapping in Barcelona and look how Brendan Rodgers and his players responded after that.”