Martin O’Neill did not dismiss the idea that Celtic have struggled to deal with adversity in Europe after the 2-1 defeat to Celta Vigo.

But the game changed quickly.

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Javi Rodriguez headed Celta level from a free-kick, before scoring again minutes later from distance after Celtic failed to clear their lines.

It was another European night where Celtic had a spell of promise, but could not handle the turning point once it came.

Asked after the match whether there was an issue with dealing with adversity when games become difficult, O’Neill did not shut the suggestion down.

He said: (BBC Sport), “I’m not sure about that.

“I’m really genuinely not sure about that, and I’ll have to really look at it again.

“It was a blow to us because we were doing fine.

“We’ve taken the lead in the game. And there’s small margins. There really are small margins.

“You may well have a point, but I would have to look at that.”

Celtic did not lose control straight away after Baur’s goal. They had a chance to make it 2-0 when Liam Scales hit the bar from a corner, and Benjamin Nygren had already forced Ionut Radu into a good save.

O’Neill also admitted elsewhere that his side should have stayed calmer after conceding.

European games will turn. Opponents will have spells of possession. Setbacks are unavoidable. The problem for Celtic is how quickly one setback became two goals.

The defeat leaves Celtic with no points from three Europa League games and second bottom of the league phase table.

O’Neill may want to watch the game back before making a firm judgement, but the question is now there: when the pressure comes in Europe, do Celtic have enough control to deal with it?