AFTER they had emitted the longest sigh of relief likely to be heard at Parkhead all season, there were two thoughts to comfort Celtic about where they stand on the tightrope between Champions League oblivion and the group stage.

Firstly, Kris Commons's unanswered goal 13 minutes from time won the sort of sticky, awkward first leg which could have drifted away from them. Secondly, they have won four of their last seven away games in the Champions League. They do not travel to the Boras Arena next Wednesday encumbered by the baggage of that once awful European record outside Parkhead. Elfsborg have lost only one of their last 25 home matches but they will have to open up a little after a night at Parkhead in which they defended tenaciously but hardly threatened beyond a couple of first-half chances for Anders Svensson.

Celtic came into the match fearful their on-loan forward, Mo Bangura, would return to haunt them. That was unfounded, although he gave Kelvin Wilson and Efe Ambrose plenty of work to do as the jeers rained down from the stands. Just when Celtic seemed to have punched themselves out, and frustration was bubbling up, Emilio Izaguirre whipped over a cross and Commons connected with the header which won their seventh consecutive qualifying tie.

It was all the more welcome after a performance which was off-colour. There was little of the cohesion and purpose which characterised last season's European run and too many errors. They failed to control passes or overhit them. Their touch was lacking and there was little rhythm to their play. When Wilson tried a silly backheel across his own six-yard box Celtic held their breath, but they got away with it.

Bangura did not do any damage near goal but he was physical and awkward and won more challenges than he lost. He threatened once with a low, rifled shot easily held by Fraser Forster. The real fright came when he held off the Celtic defence in the box and helped ferry the ball into the path of Svensson, who cracked a fierce shot off the bar. When the Elfsborg captain then met a corner with a close-range header just over the bar the stands voiced a low rumble.

At 37, Svensson was the oldest player on the pitch and one of five Elfsborg players of 30 or more. Their experience showed in the way they held their shape and their nerve, and in the way they roughed up Celtic's players without getting any of their own sent off by the Portuguese referee. They were aggressive and spirited, but limited too. Celtic did expose them long before scoring.

They opened up the Swedes' defence after only 13 seconds when Samaras nodded the ball on for Anthony Stokes to hook a shot across goal from a tight angle. Long, diagonal passes twice found James Forrest in space on the right and from one of those his shot glanced off the face of the bar. Stokes had the ball in the net, but was offside. Ambrose fluffed a great chance from a corner. Stokes had a free-kick tipped over.

It all made for a compelling, open match, but that is not what 40,153 fans were here for. They wanted victory and they wanted reassurance. Eventually the former was delivered, if not quite the latter.

Georgios Samaras and Forrest could not get on the ball enough in the wide areas and Commons was usually smothered by Elfsborg's diligent, tough defending. When he beat a man or two there would be another snapping in to frustrate him. When Samaras spun a defender his runs would be ended either by a firm tackle or a foul. Both James Keene, Elfsborg's English midfielder, and Johan Larsson scythed him during one dribble and although he rode the first challenge the second brought him down and earned a booking. Stokes jabbed a short pass which put Samaras in, but for once his scoring touch deserted him and he shot straight at Kevin Stuhr-Ellegaard. The goalkeeper coped with nearly everything which came at him, including numerous Celtic crosses.

When they were not being tripped or brought down by niggly fouls – Elfsborg earned four bookings to Celtic's one – the home side cranked up the pressure as the second half wore on. Elfsborg defended deeper, to the point Bangura was so isolated he was forgotten about until inflaming the crowd by clutching his face after an untidy tussle with Wilson.

Still Celtic laboured. Samaras drove a low ball across the box which struck Daniel Mobaeck and deflected inches outside his own post. It was as close as they came until the goal. Izaguirre delivered a delicious cross to the back post and Commons rose to finally beat Stuhr-Ellegaard.

The relief was palpable. When some fans tried to start a late "huddle" it did not take hold. The mood wasn't right for that. Too many supporters were wary of turning their backs on the pitch. They know, too, that Celtic have yet to see the back of Elfsborg.