It took a header from Kris Commons in the 76th minute to give Celtic a slender lead in Glasgow and a 1-0 win to build on in Sweden next Wednesday.
The stubborn visitors frustrated Celtic for long periods of the play, routinely putting all 10 outfield players behind the ball. The scoreline also reflected Celtic's own missed oppurtunities, with the Glasgow club lacking sharpness upfront without the presence of Gary Hooper.
The Swedish team started off the brighter of the two, with Stefan Ishizaki firing wide in the first minute, and Celtic's Bangura, playing on loan for the Swedish club, testing his own team with a low shot stopped by Fraser Forster.
Celtic were relativily uncomfortable in the opening stages, taking twenty minutes to carve a real clear cut chance, when James Forrest latched onto Kris Common's long ball, but the Celtic winger's effort bounced up onto the bar. Minutes later, the largely ineffective Anthony Stokes had the ball in the back of the net, but the linesman's flag was upright.
It was Elfsborgs turn to scare Celtic a few moments later when Anders Svensson's fantastic strike rattled the Parkhead crossbar amid panicked gasps around the stadium. Moments later Efe Ambrose met Kris Commons' corner with his head, but failed to hit the target.
In the second half, Celtic started to exert control on their Swedish opponents, but still lacked that killer touch in front of goal, with Georgios Samaras a constant menace. Despite Celtic's dominance, Elfsborg seemed intent on slowing the game down at all oppurtunities. Mo Bangura may have to hide his face if he has to return to Celtic Park after his loan spell, having gone down in a heap clutching his face on two seperate occasions, to the annoyance of the Celtic support, who booed him throughout.
It took Celtic until the 76th minute to find the breakthrough, and the goal came after a prolonged period of pressure. Emilio Izaguirre cut inside onto his weaker right foot and floated a cross over all of the Elfsborg defence, with Kris Commons unmarked at the back post, sending his header downward past the keeper.
Celtic kept the pressure on, but couldn't break the Swedes down again, and will have to settle for a one goal advantage over in Sweden in next weeks second leg
Man of the match - Georgios Samaras