A goalless draw at Qarabag was enough to see Celtic into the next round of the UEFA Champions League.
Celtic sealed their progression to the play-off stage of UEFA Champions League qualifying with a drab goalless draw at Qarabag on Wednesday.
The Scottish champions led 1-0 from last week's first leg in Glasgow, in which Dedryck Boyata found the net, but rarely threatened to add to their slim advantage at the Tofiq Bahramov Stadium in Baku.
Indeed it was Qarabag who posed the bigger threat for the most part, Craig Gordon leaping to his right to keep out a Richard Almeida strike midway through the first half.
But the hosts lacked the required quality in the final third and failed to punish a lacklustre Celtic display, although - in defence of Ronny Deila's men - they did not need to score and will not concern themselves with the manner of their progression in difficult conditions.
Much had been made of the state of the pitch in the build-up to the fixture, with the playing surface having endured soaring temperatures in the Azerbaijan capital, but stadium bosses - with the help of a Scottish groundsman - managed to bring it up to a playable standard.
And it was the home side who took control early on, although Reynaldo's use of an arm spelt the end of a promising opportunity after eight minutes.
Qarabag continued to look most likely to break the deadlock and, after seeing Gordon flap at a cross from the right moments earlier, Almeida drew a superb diving save from the Scotland international with a strike from 20 yards out.
Players were afforded a drinks break on the half-hour mark to combat the impact of the heat, but the hosts' thirst for an equalising goal in the tie remained unquenched at the break.
Alharbi El Jadeyaoui failed to test Gordon with an attempted chip shortly after half-time, before Nadir Ciftci curled over from the edge of the box at the other end following some neat build-up play.
Chances remained few and far between as hopes of an upset began to fade for Qarabag, but they saw calls for a penalty rejected when an apparent Boyata push went unpunished.
Stefan Johansen poked wide for Celtic in the closing stages, yet that miss did not come back to haunt them as Deila's side held on for an aggregate victory.