Rangers manager Mark Warburton celebrates winning the Scottish Championship with the trophy
Quoted by Inside Futbol, Rangers legend Peter Lovenkrands has suggested that Celtic have taken "massive step back" in recent years.
Rangers are set for a Scottish Premiership return next season after four years slugging it out in the lower divisions following their exile in 2012.
Celtic manager Ronny Deila
In this time, Celtic have dominated domestically, winning five successive Premiership titles - three under Neil Lennon, two under Ronny Deila - but the Hoops have struggled to make headway in Europe.
Under Deila, they never reached the Champions League proper, and finished rock bottom of their Europa League group in the 2015-16 campaign for what is thought to have contributed to Celtic's decision not to extend his contract.
The Rangers icon says the Gers have taken a "massive step forward" since their demotion four years ago in words which is sure to antagonise those on the other side of the Old Firm divide.
"For me Celtic have taken a massive step back. When I was at Rangers and played against Celtic they were also quite dominant in Europe and went to the Europa League final and all these different things", he said to Rangers TV, via Inside Futbol.
"They used to be a force at Parkhead and not be beaten. They've been terrible this season.
"They have taken a massive step back and we've taken a huge one forward. They didn't spend a lot of money because they thought with Rangers not there to compete with them they had it in the bag anyway.
"It's hurt them in Europe and now they've taken a massive step back."
Although parts of his spiel may ring true, the truth is that Celtic have made a huge statement with their appointment of Brendan Rodgers.
It is a wonderful signing, one which will draw plenty of star power to the green part of Glasgow. In any case, it'll surely be a cracking Premiership campaign next term, with Rangers signing the likes of Joey Barton and Jordan Rossiter already this summer.
Celtic - Brendan Rodgers Press Conference