Celtic's European ambitions were left in ruins after the Scottish champions squandered a commanding four-goal aggregate advantage to fall to a stunning 5-1 defeat away to LASK, sending the Austrians through to the Champions League league phase and Celtic into the Europa League for a second consecutive season.
The night began promisingly enough in Linz when Callum McGregor extended Celtic's aggregate lead to 4-0 with a deflected effort in the 21st minute, capitalising on a slick one-two between Yang Hyun-jun and Kieran Tierney before drilling the ball home off a defender. Chances continued to fall Celtic's way, with Mika Baur and Kasper Hogh both testing the visitors' resolve at the other end without success.
But the tie turned dramatically just past the half-hour mark when sloppy possession from Benjamin Nygren gifted LASK an opening, allowing Moses Usor to pounce and halve the deficit on the night. From there, the home side's momentum proved unstoppable.
Three minutes into the second half, Usor muscled past Auston Trusty and squared for Robert Ljubicic, who rifled a 20-yard strike beyond the Celtic goalkeeper. Worse followed in the 58th minute as Samuel Adeniran curled a stunning first-time effort into the top corner from 25 yards, leveling the aggregate score and throwing the tie wide open.
Celtic goalkeeper Viljami Sinisalo kept his side afloat with a string of vital saves, denying Sascha Horvath before Joao Victor Tornich headed inches wide from the resulting corner. Adeniran also struck the underside of the crossbar as LASK poured forward relentlessly. Manager Martin O'Neill was forced into defensive reinforcements, bringing on Liam Scales and Dane Murray to form a back four alongside Trusty and Cameron Carter-Vickers, while Luke McCowan, Reo Hatate and Sebastian Tounekti also entered the fray from the bench.
Despite Sinisalo's heroics, including another crucial stop from a Tornich header, LASK snatched a stoppage-time equaliser on aggregate when Florian Flecker converted the rebound to force extra time. Carter-Vickers, battling cramp throughout, was eventually replaced by Anthony Ralston as O'Neill used his additional substitution allowance in the extra period.
Celtic appeared to have weathered the storm as the additional 30 minutes wore on, but Adeniran delivered the decisive blow five minutes from time, dispossessing McCowan before drilling home from 25 yards to complete a remarkable individual and collective turnaround for LASK. Sinisalo denied the striker a hat-trick with a penalty save late on, but it mattered little as the Austrians held on to seal a 5-4 aggregate victory and book their place in Europe's premier club competition.
The result represents one of the most dramatic collapses in Celtic's European history and compounds a difficult run in continental competition for the Scottish champions, who also exited at the play-off stage on penalties last season following a goalless tie with Kairat Almaty. Questions will inevitably be asked about the club's transfer business, particularly the decision to sell midfielder Arne Engels shortly before the first leg, with Celtic losing their grip on midfield battles in Austria.
While Celtic's finishing had proven decisive in the first leg in Glasgow, LASK created a wealth of opportunities across both matches and ultimately made their pressure count when it mattered most, condemning O'Neill's side to Europa League football and a £20million-plus financial blow.
Based on reporting from Independent Football, Guardian Football, and Standard Football.