Celtic have maintained their hopes of qualifying for the group stage of the Champions League by edging out Rosenborg 1-0 in the third qualifying round.
Following last week's goalless first-leg draw in Glasgow, James Forrest's precious strike off the underside of the bar 21 minutes from time proved the difference in Trondheim as the Bhoys made it through to the playoff round.
The draw for the next qualifying stage will take place in Nyon on Friday, with Celtic now just one step away from booking their place in European football's showpiece competition for the second year running.
Rosenborg looked to get at their opponents from the off, but it took until 15 minutes in before Craig Gordon was called into action to keep out Milan Jevtovic's weak attempt.
Scottish champions Celtic so nearly bagged the away goal they were after moments later when Erik Sviatchenko climbed highest to meet Jonny Hayes's free kick, only for Niklas Bendtner to nod off the line.
That would prove to be Sviatchenko's last involvement on the game due to a collision with Anders Konradsen, but Celtic remained alert and were looking the more likely to net the opening goal of the tie.
Forest was denied by Andre Hansen after being teed up by Scott Sinclair, before Scott Brown's long-range attempt was kept out in a fairly routine manner.
Bendtner called Gordon into action for a second time shortly before the interval, as the Norwegian pacesetters struggled to truly create any sort of big openings.
Yann-Erik de Lanlay had a chance to change all that soon after the restart, running on to a Bendtner pass but slipping the ball wide of the target.
The match was beginning to become more and more stretched as the hour mark approached, with Kieran Tierney and Mike Jensen both coming close for their respective sides at either end of the field.
Celtic's big moment arrived with 69 minutes on the clock, as Forest got on the end of Sinclair's pass and this time thumped it past Hansen to score what would prove to be the killer goal.
Substitute Leigh Griffiths came close to adding a second in the remaining minutes, seeing his shot deflect narrowly wide, while Forest was to be denied by Hansen when one-on-one.
In the end Forrest's drive proved enough, though, meaning that Rosenborg drop into Europa League qualifying while Celtic march on.
Daniel Lewis
