Celtic vs Stjarnan match report: Ronny Deila's limited Champions League hopes justified by laboured Hoops

Celtic 2 Stjarnan 0: Scottish champions fail to impress in first-leg against Icelandic part-timers

Dedryck Boyata opens the scoring for Celtic with a powerful header (PA)

Celtic manager Ronny Deila says that simply reaching the group stage of the Champions League should be considered success for Celtic; those who question his ambition were woken by the reality of this performance. Deila might be right.

Against the Icelandic part-timers of Stjarnan, Celtic will take a moderate advantage into the second leg of their second qualifying-round tie next week, and if Deila’s team hold onto it on an artificial surface, they will need to improve sharply once the opposition toughens.

Admittedly this was Celtic’s first game of the season, but there was plenty wrong with it. Goals from Dedryck Boyata and Stefan Johansen cannot camouflage that. There was also a penalty miss from substitute Leigh Griffiths.

Gunnar Nielsen, Stjarnan’s keeper, made four good saves but then he was expected to: such were the odds, at kick-off it seemed sensible to look up Celtic’s record score in Europe. Forty minutes in, it was relevant to check on Celtic’s worst European night.

That was an indication of how the first half had unfolded as their intricate build-up play dissolved on the edge of the Icelanders’ area or was frustrated by Nielsen.

Then, in the 44th minute, Boyata, making his debut following his £1.5m sale by Manchester City, met Johansen’s far-post cross. From four yards out, Boyata’s header was unstoppable.

It was not a dream debut for Celtic’s big summer signing, Nadir Ciftci, who had a couple of half-chances but was replaced after 74 minutes.

Yet it could have been worse. In four second-half minutes Stjarnan missed two good chances before Stuart Armstrong on the Celtic left fed the ball diagonally into the path of Johansen, who flicked the ball neatly beyond Nielsen.

Celtic have a two-goal cushion. But they have work to do.