AS the half-time whistle blew and Rangers retreated to the dressing room, the mood within Ibrox was not reflective of a club just 45 minutes away from their greatest European result in modern history.

Borussia Dortmund trailed 5-4 on aggregate, but the combined intensity and ability of their response to James Tavernier’s opener from the penalty spot granted control of the momentum. Jude Bellingham’s leveller on the night was fortuitous, unlike Donyell Malen’s strike soon after which carried with it an air of inevitability that more goals may follow.

German attacks see-sawed between either flank as the home defence struggled to control their opponent’s ventures. Rangers weren’t doing all that much different from the reverse tie; they looked to press high whenever possible, condense the space their opponents could play within and utilise a high line. Unfortunately, Marco Rose had changed course to good effect.

The visiting manager was able to reintroduce Thomas Meunier at right-back which offered natural width and often a clear attacking outlet beyond pressure. On either flank the wide triangles rotated quicker than Rangers could react and play regularly switched sides. They were able to earn space in moments of transition that hadn’t appeared the week before and although Scott Arfield’s guilt-edged chance could have punished the weak Dortmund rearguard, Allan McGregor was called upon twice to make big saves.

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Was this period before the break a natural turning of the tide, in a tie that on the basis of resources Rangers had no right to win?

The task for Giovanni van Bronckhorst in the half-time dressing room was to decipher the Dortmund approach and limit their advances, without totally negating his side’s attacking weapons. Sitting back for 45 minutes wasn’t an option and the crowd which had brought such energy from the start needed refuelling with a foray or two up the park. Luckily, he was prepared for such eventualities.

The solution was a pre-ordained system worked on ahead of the tie, one of “three scenarios ready to be implemented” according to the manager. John Lundstram joined Leon Balogun and Connor Goldson to form a back three as Calvin Bassey moved to wing-back alongside James Tavernier in a 3-5-2, which carried the multifaceted threat of Alfredo Morelos and Ryan Kent up top.

“I think we were much more solid defensively and when you play this system you have to be ready for the moments in transition which we really did,” van Bronckhorst said of the formation switch.

Neutralising the Dortmund threat and stemming the tide was the priority, albeit slender, the hosts still had a lead to hold onto. However, it was the liberated front line that won out thereafter as Rangers remembered what had brought them such success in this fixture previously, attacking Dortmund's vulnerabilities.

Morelos and Kent played as a pair, matching up against Emre Can and Mats Hummels, the latter of whom had floundered when facing the Colombian in the reverse tie. While the visitors grew frustrated and threw more forward in search of an equaliser, Rangers could retain their offensive threat in transition – in van Bronckhorst’s words the Morelos-Kent combo "changed the game”.

Morelos was immediately sought out after the break and as bustling brilliance allowed him to break beyond Hummels, the energy sapped out of the stadium just before the interval was reinjected. Kent too could run at the heart of a messy back four and had a goal chopped off later in the tie, liberated from defensive responsibility and hanging on the last man.

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Bassey and Tavernier regained control of the wings and would link to score the tie’s final goal. The left-back, who has grown substantially as a player this season, displayed determination and skill to deliver a cross Hummels missed, Tavernier’s attacking freedom granted him permission to be at the back post, ready to convert. His contribution throughout was immense. 

The in-game alteration showed the benefit of variety. Just as Dortmund’s differentiation from the start brought success in the early stages, they were forced to adapt their strategy once van Bronckhorst recalibrated his troops. Rose conceded the change “made it quite difficult” for his side. Would victory have followed if nothing had changed from the sidelines?

Moments of intervention were still required and in flashes Dortmund’s quality reappeared. Bellingham in particular drew anxious breaths when in possession, playing with a maturity and poise well beyond his young 18 years.

The hosts would hold strong and over the course of both legs they were entirely deserving of a 6-4 win. Suffering from teething problems or not, this Dortmund side were tournament favourites at the start of the year and sit second in the Bundesliga for a reason. For each vulnerability Rangers exploited, the opposition had a weapon that needed neutralising.

The sound of ‘I’m Feeling It’ earned a cheer from supporters after the full-time whistle, a song becoming synonymous with important Ibrox victories. An atmosphere for the ages had been generated throughout and fans remained behind to share a moment with their team. Ryan Jack and Arfield danced in front of the Broomloan, Tavernier saluted all four stands, Goldson stood just soaking it all in.

It may take time to register the feat of this triumph, in the immediate aftermath the only thing that mattered was celebration.