MIKEY Johnston’s impressive pre-season form continued spectacularly in Sarajevo when he scored the best goal of his career so far and at a perfect time as well, which completely turned a potentially difficult night in Celtic’s favour.

Just as Neil Lennon and the Celtic supporters may have started to worry that it was going to be one of those awkward early European ties, the 20-year-old superbly found the Bosnians’ net from 25 yards and more, a wonderful moment on which this victory was built upon.

The return next Tuesday will surely be a formality.

FK Sarajevo had taken the lead just before the half hour on a treacherous, wet night in the Bosnian capital. The home support, going by the noise, certainly began to believe and while it only took six minutes for Celtic to equalise, that was enough time for a few nerves to form.

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You know the old cliche of a certain moment in a match being “a good time to score” as if there is a wrong time; well, the 35th minute of this first-leg qualifier just so happened to be perfect for Celtic. After that, there was only going to be one winner.

These qualifiers are always the same. Celtic play OK, look a bit rusty, a few don’t look fit enough, but they get through it. Lennon would have been happy enough.

There was a debut for £3m signing Boli Bolingoli-Mbombo who had a mixed evening which ended early in the second-half when he limped off the field with an injury. The summer’s big buy so far, centre-half Christopher Jullien, was on the bench and while new faces are always welcome, so, too, are old ones who had become less familiar.

The sight of Leigh Griffiths warming up as a substitute warmed the heart, as did Ryan Christie being in the starting XI, his first game since being knocked unconscious on April 14 in the Scottish Cup semi-final with Aberdeen.

Sarajevo sat deeper than might have been expected in the opening stages, happy to allow Celtic to pass the ball about, waiting for a mistake, which duly came eight minutes in.

James Forrest was unusually slack with a pass, possession fell the way of Slobodan Milanovic whose long ball over the top found Sarajevo’s best player, Anel Hebibovic, who proved faster than Mbombo.

Celtic looked for an offside flag which never came and for a second or two, with Hebibovic favourite to reach the ball first, a goal seemed the likely outcome; however, Scott Bain read what was happening, he got off his line and made a superb block.

HeraldScotland:

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Celtic hummed and hawed. They got wide as much as possible, doing better on the left, Forrest always had two men to beat, but when the crosses came from Johnston and Mbombo, good as they were, they never hinted that they would lead to a goal.

And then on 29 minutes, Celtic lost one from a needlessly conceded corner, followed by the inability to defend a corner. This is hardly a new flaw. A ball into Celtic’s box was headed past Jozo Simunovic, he and Bain were not on the same page, and when it comes to a set-piece on the European stage, even the smaller teams cause problems to the Scottish champions.

The corner from Milanovic wasn’t blocked or cleared, and Oremus slotted put the loose ball into Celtic’s net and then celebrated as if he’d just won the Champions League.

The lively Christie at least had a couple of shots but Celtic had not looked threatening at all. Thank goodness, then, for young Johnston.

The 20-year-old pirouetted in the centre of the park, got past a few tackles and got his perfect shot on target from distance. A huge moment for a player who it is hope will make his proper breakthrough this season.

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So far, so excellent for the latest academy product. Sarajevo, on and off the park, went to pieces. It was rather odd to experience.

Celtic dominated from that moment on. Odsonne Edouard sprang to life before half-time, took a couple of defenders out of the game to give Forrest a shot at goal with the right side of his foot, a speciality, but his effort was just over.

And then the tie was all but over six minutes after the break.

Edouard really is quality even if there are times he can be frustrating. Scott Brown made the most of a loose ball, the captain fed Forrest who fired a pass into the Frenchman and he superbly delayed his shot, a dummy everyone in maroon bought, and then chipped home. As soon as Celtic’s main striker got himself in position, there was an inevitability that he would score. At 21, this young man is already a serious talent.

With five minutes to go, Lewis Morgan’s fine cross was missed by Edouard but not by Scott Sinclair who back-heeled the ball home for a lovely third goal. Job well and truly done.