Celtic opened their Europa League Group D campaign by drawing with Salzburg at the Red Bull Arena.
On-loan Rubin Kazan winger Wakaso Mubarak drilled home the opener in his first Celtic appearance.
Brazilian Alan levelled with the aid of a deflection as the visitors were caught short in defence.
Ramalho Silva diverted Scott Brown's volley in for Celtic's second but a superbly struck Jonathan Soriano free-kick levelled matters once again.
And, with Dinamo Zagreb beating Astra Giurgiu, Celtic and Salzburg trail the Croatian side by two points after the first round of matches.
Wakaso had waited several weeks to make an impact with the Scottish Premiership side after manager Ronny Deila was frustrated in his attempts to have the player signed before their Champions League play-off defeat by NK Maribor.
The Ghana international provided a taste of what was to come when he struck low past Peter Gulacsi's goal.
And with his next effort the 24-year-old arrowed the ball across the goalkeeper and into the corner from Kris Commons' pass.
Such an early set-back was the last thing Salzburg needed after three successive domestic defeats and there was little to encourage the home fans until Ramalho got on the end of a teasing Soriano free-kick.
The Brazilian peeled off to the back post and rose unchallenged to send his header goalwards, Gordon getting a vital touch to knock the ball wide.
Celtic's early season defensive struggles - no clean sheets in their previous six games - were apparent as Jason Denayer slipped at the vital moment for Salzburg's leveller.
Alan was allowed to run on to Kevin Kampl's pass and though Efe Ambrose got across from the right the defender succeeded only in redirecting the eventual shot past Gordon.
Salzburg's confidence grew and Marcel Sabitzer fired wide before Gordon was given more work to do in the second half.
Alan's strike was blocked and the Scotland international produced a double save to keep out Sabitzer's shot and Alan's rebound header.
However, the hosts had their own defensive vulnerabilities and Stefan Scepovic had tried to take advantage with an ambitious dipping shot from wide on the right that landed just past the near post.
And Salzburg were slow to close down Brown when he hit the 25-yard shot that Ramalho's outstretched boot would carry into the right-hand corner of the net.
Again Celtic's lead did not last, however. Emilio Izaguirre fouled Sabitzer around 30 yards out and Soriano curved the ball expertly over the wall and into the top corner.
Near-misses at either end permeated the closing stages but neither side looked convincing in attack as the clock ran down.