Celtic eventually made home advantage count as Dedryck Boyata's late goal secured a 1-0 win over Qarabag in the first leg of their UEFA Champions League third qualifying round tie.
Ronny Deila's side had progressed through the second round with a comfortable 6-1 aggregate win over Icelandic side Stjarnan, but they were given a much sterner test by Azerbaijan's champions.
Nadir Ciftci failed to get in on the act against Stjarnan and the close-season signing again could not find the net, despite Celtic's most clear-cut chances landing at his feet.
Qarabag goalkeeper Ibrahim Sehic was impressive, denying Ciftci and Virgil van Dijk sharply after the interval as the hosts looked to dictate terms, but he was at fault for Boyata's 82nd-minute header getting beyond him – the Belgian scoring his second Champions League goal since joining Celtic from Manchester City.
Celtic's task is far from complete ahead of next week's second leg in Baku, however, with Qarabag enjoying a fearsome record at home, only finalists Dnipro beat them on their own turf in last season's UEFA Europa League.
Ciftci will miss the first six games of Celtic's Scottish Premiership campaign after being found guilty of biting last season and played like a man with a point to prove, regularly pulling out of position in an attempt to be involved in the game.
The Turkish striker's efforts helped open up the first chance of the game for Gary Mackay-Steven, whose low shot was gathered by Sehic at the second attempt.
It was as close as either side got in a cagey opening half, but Celtic came out with renewed purpose for the second period and were well on top early on.
Ciftci headed narrowly wide from Emilio Izaguirre's left-hand cross before the ball fell kindly for him from Stefan Johansen's set-piece, but the former Dundee United man could only lash straight at Sehic when the chance presented itself.
Sehic was becoming Celtic's nemesis as he reacted sharply to keep out Van Dijk's header from another probing Johansen delivery before the Dutch defender sent a long-range piledriver narrowly over the crossbar.
That chance prompted Deila into a change as Leigh Griffiths came on to widespread approval from the Parkhead crowd and Kris Commons also emerged from the bench.
Commons was involved in the goal as his delivery found an unmarked Boyata in the six-yard box and his powerful header left Sehic no chance after the goalkeeper rushed off his line.
