Speaking to The Mail, Rangers legend Ronald De Boer has admitted that he has always been 'amazed' by the passion generated by Celtic fans.
The Dutch legend spent four years at Ibrox, experiencing first hand the hostility between both Old Firm clubs having played in the fixture on a number of times.
The 46-year-old, of course, experienced the atmosphere at Parkhead during his stint with Rangers, and De Boer admits that such an occassion was "amazing", noting the "fanatical" Celtic fans for playing a big role in the derbies.
"I have great memories of all the Old Firm games I played in — even the losses," the Rangers legend said to The Mail.
"The intensity of the games was amazing. I loved to play at Celtic Park, one of the best stadiums in the world.
"When you have 67,000 fanatical Celtic fans it was amazing to be a part of it. I loved every minute."
Next season will see the return of Old Firm games on a much more regular basis, with both sides only squaring off on two occasions since 2012 - Rangers winning and Celtic winning one.
The landscape of Scottish football may be shifted in favour of the Gers, who look a serious threat under Mark Warburton and Bhoys supporters may be somewhat concerned.
Their season isn't even over and they have already got their summer business underway, recruiting Jordan Rossiter from Liverpool, while Premier League veterans Joey Barton and Niko Kranjcar are said to be heading to Rangers, too.
De Boer won one Scottish Premiership title and two Scottish Cups during his spell with Rangers, which ended in 2004.