Borussia Dortmund underestimated Rangers on Thursday, believes Derek McInnes, but the former Ibrox player has warned his old side the Germans won't make the same mistake twice.
Gio van Bronckhorst's side took a stunning win in the first leg of their Europa League play-off, running out 4-2 winners in the Westfalenstadion.
They'll have home advantage in the second leg and the backing of 50,000 Rangers fans as they look to pull off one of the greatest results of the modern era.
But while McInnes was blown away by the quality on show in Dortmund in the first leg, he feels the hosts underestimated the Scottish champions.
And the Kilmarnock boss has warned the tie is far from over, especially with Erling Haaland potentially returning and no away goal rule.
Writing in his Mail on Sunday column McInnes said: "Rangers would have taken any kind of positive result from their game away to Borussia Dortmund, knowing they would be coming back to play at a full Ibrox.
"But to go to Germany and score four times is an unbelievable achievement, and that 4-2 scoreline stands alongside any European away result in modern times.
"Dortmund clearly underestimated their opponents and Rangers forced the issue.
"Alfredo Morelos played like a proper centre-forward. He was bright, busy and hard-working and got the press right. He can occupy a full back four when he is in that mood. Mats Hummels looked a bit shocked at the calibre of his play.
"He had good support from Joe Aribo, Scott Arfield and Ryan Kent, who really looked in the mood. When Kent performs to that level he can be such an influence.
"My regard for Ryan Jack is well documented and on Thursday he was the best midfielder on the pitch.
"It was a proper team performance but Giovanni van Bronckhorst will be wary.
"You only need to hear Michael Zorc speak of how Dortmund want the Europa League to make up for the lost revenue from the Champions League.
"For Rangers to take that kind of scalp would be a fantastic achievement and I'm delighted for Giovanni, who set the team up well and also made good substitutions.
"Dortmund certainly won't underestimate Rangers again and there will be plenty of people out there who will fancy them to come and win by the required margin in Glasgow, especially if they can get Erling Haaland back from injury.
"Rangers have proved they can stand up to Dortmund... now they have to do it again."
