For Celtic a night which could hardly have started any better went downhill fast. A vaguely familiar second half witnessed the loss of three goals and winger James Forrest to a red card.
Proof, if it was needed, that much Red Bull causes palpitations.
Odsonne Edouard’s first goal in eight games came after a minute and 39 seconds. A strike of strength and composure, it gave Celtic the perfect start.
Kieran Tierney’s defensive header was hooked up the left touchline by Callum McGregor in hope rather than expectation.
As Andre Ramalho lost the ball in mid-air, Edouard outmuscled the hesitant No 15 to power his way into the area and sidefoot a composed finish low into the far corner. Celtic could hardly believe it themselves.
The night followed a familiar pattern away from home in Europe in the end.
The home team blew Scotland’s champions away with second half goals from Japanese striker Takumi Minamino and two for top scorer Munas Dabbur, the second a spot-kick after Forrest was shown a red card for denying Salzburg captain Andreas Ulmer a goalscoring opportunity.
Edouard’s goal proved a false dawn in the end. Celtic came here without captain Scott Brown, playmaker Tom Rogic and central defenders Filip Benkovic and Kristoffer Ajer in the starting line-up.
Youssouf Mulumbu, the former Kilmarnock midfielder made his first European start in midfield. It serves no purpose for supporters to climb on Jack Hendry’s case all the time, yet a harsh truth is becoming hard to avoid. For Celtic to defend properly at this level they need £13million loan defender Benkovic fit and they need him fit fast.
Defeat here edged Marco Rose’s team top of Group B on six points, RB Leipzig beating Rosenborg in the other game to join Celtic on three points after two games.
It also extended Celtic’s winless record away from home in the Europa League to 13 games and means Celtic still await their first win on Austrian soil after six attempts.
Expectations were always low here. RB Salzburg hadn’t lost in their home arena since a defeat to Admira Wacker in November 2016 – almost two years.
Yet the sense of anti-climax was intense in the end, heightened by a dream start followed by a familiar and depressing collapse.
Returning to a role he’s comfortable with, coming in off the left, Edouard’s return to scoring form gave the Parkhead side something to cling to. Brendan Rodgers used the pre-match press conference to promise a compact, solid performance.
As the fancied home team laid siege to the visiting goal when they had to be.
Takumi Minamino’s firm header failed to hit the target. Top scorer Munas Dabbur played a delightful one-two at the edge of the area and struck his first time shot wide of Gordon’s right hand post.
As the half wore on Celtic grew deeper and the first half possession stats told no lies.
Salzburg had 60 per cent of the ball, the team in green and white finding it harder to retain the ball.
Yet Celtic thought they had a second goal two minutes before half-time.
Edouard again burst into life, bulldozing his way into the area before laying the ball off for James Forrest to drill a low shot at goal. Salzburg keeper Alexander Walka saved, but couldn’t prevent the £9m man bundling the ball into the net from close range.
Rightly, the offside flag stilled the premature celebrations of the travelling support.
At half-time Celtic could take refuge in the one statistic that mattered. They had the only goal of the game.
That could have changed within a minute of the restart. RB Salzburg noticeably upped the tempo.
A deft through ball from Hannes Wolf sent the lurking Dabbur through on goal, Craig Gordon racing from his line to block with his legs, Mikael Lustig heading the dropping ball out of the sky to safety.
For Celtic it threatened to be a long and testing 40 minutes or so. A half when concentration and retaining the ball a little better would prove beyond them.
Salzburg’s equaliser began to look mildly inevitable and arrived 10 minutes into the second half. Foiled by Gordon once, Dabbur wouldn’t be denied twice.
It was a cheap goal for Celtic to lose, Minimino’s header towards the back post turned back across goal for the number nine to direct it into the net under Gordon’s body with his left foot.
Celtic’s midfield were visibly fading, all but incapable of getting and holding the ball.
Brendan Rodgers threw Scott Sinclair on for Leigh Griffiths and the winger had only been on the pitch seconds when Red Bull took the lead within five minutes of the equaliser.
Captain Andreas Ulmer made headway on the left touchline, slotting Xaver Schalger’s pass into a crowded area first time. The ball landed at the feet of Minamino, the striker digging the ball from under his own feet to hold off Jack Hendry and nudge it into the net from close range.
For Celtic the night went from bad to worse when James Forrest conceded a penalty and a red card for denying Andres Ulmer a goalscoring opportunity inside the 18-yard box in 71 minutes.
Dabbur swept the penalty down the middle of goal, Gordon diving to his right.
Two goals and a man down the worry for Celtic was obvious. This was now a game with the potential to end messily. The visitors were clinging on.
Salzburg substitute Zlako Junuzovic curled a 20-yard strike wide of Gordon’s right hand post with the Celtic keeper scrambling. The same player was denied by the post moments later. The only saving grace for Scotland’s champions in the end was the fact they stopped at three.