Mission not impossible, but Celtic and Hibs don't have history on their side in bid to overturn three-goal deficit
In 55 years of European competition, Scottish clubs have a poor record of second-leg home victories when their opponents have a lead of two or more goals from the first leg.
Sporting Braga will come to Parkhead confident that they can complete their Champions League qualifier and Hibs have a mountain to climb in the Europa League qualifier against Maribor, as halfway aggregate scores of 0-3 in both cases make grim reading for Scottish football statisticians and fans of both clubs.
In their long European football history, Celtic have several times come from behind after a first-leg defeat to win through at Parkhead, but never when that deficit was three goals.
The most famous reversal of fortune was against Vojvodina Novi Sad in the 1966-67 European Cup winning run when Billy McNeill scored late on to make it 2-0 and put Celtic on the road to Lisbon 2-1 on aggregate. Two seasons later, St Etienne beat Celtic 2-0 in France, but Celtic scored four without reply at home.
There is a glimmer of hope in Celtic's record against Portuguese clubs. In the 1983-84 UEFA Cup, Sporting Lisbon won 2-0 in Portugal but were brushed aside 5-0 on a night when Celtic had five different scorers.
The following season's Cup Winners Cup saw Celtic go down 1-3 to Rapid Vienna in Austria, but on a controversial night at Parkhead the winning score line of 3-0 meant nothing as a thrown bottle saw UEFA order a replay that Rapid won 1-0.
Heavier away defeats, such as the 1991-92 UEFA Cup debacle when Celtic lost 1-5 to Neuchatel Xamax in Switzerland and the infamous 0-5 loss to Artmedia Bratislava in the 2005-06 Champions League, saw futile attempts to claw back goals.
Neil Lennon will no doubt take comfort from that Bratislava tie as Celtic did score four at Parkhead and went on to lift the first of Gordon Strachan's three SPL titles, but he would surely love to see a performance like that of Kilmarnock in their first ever European tie.
Back in 1964, Kilmarnock were in the Fairs Cities Cup, forerunner of the UEFA Cup, and travelled to Germany in hopeful mood, only to return as victims of a 0-3 skelping. Manager Willie Waddell sent his men out to attack at Rugby Park, and they promptly went another goal down.
Kilmarnock, who would become Scottish champions that season, then turned on the power and two goals from Ronnie Hamilton and singles from Brian McIlroy, Jim McFadzean and Jackie McInally gave the Scottish club a 5-4 aggregate victory.
Arguably the best comeback in Europe was by none other than Hibs, and, club fan that he is, manager John Hughes will no doubt be inspiring his players with the story of how the Easter Road side conquered Napoli - Dino Zoff and all - in season 1967-68.In the Fairs Cities Cup, Hibs were trounced 1-4 in Italy, but unanswered goals from Bobby Duncan, Pat Quinn, Peter Cormack, Pat Stanton and Colin Stein gave Hibs a phenomenal 6-4 aggregate win .
Stanton said: "We felt we could beat them at Easter Road - but maybe not in the manner we did.
"When we scored the first goal and got it to 4-2, we all thought 'oh, wait a minute here, we can do this' and we went on to have a fantastic 90 minutes for the club.
History may be against them, but Celtic and Hibs have made some history themselves in the past. They will need to do so again this week.