CELTIC have quickly learned that in the Champions League, talk is cheap, and lapses are expensive. Alas, that same old feeling of deflation was all too apparent around Celtic Park following another defeat at the highest level in midweek, that was at least - in part - brought upon themselves.

A failure to turn spells of domination into meaningful advantages, and a propensity for switching off at crucial moments, does not an elite European side make.

The Celtic manager knows this. The players certainly do. But putting that knowledge into practice is still just proving a little difficult for them to master.

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The players are fed up speaking about it, too. But in order to see the back of such wearily familiar post-match post-mortems, putting their lessons into practice is what they must aim to do when they take on Atletico Madrid at Celtic Park at the tail end of the month.

Greg Taylor, having been a part of campaigns over the last two seasons that have so far offered little beyond hope off the back of some decent performances, acknowledges that the time for talking when it comes to this wretched run of Champions League results is just about over.

“I hate speaking about what ifs, but that’s how it feels,” Taylor said.

“The size of the club deserves more than to be coming close, we want to be actually producing at this level.

“The first two group games have shown we can do that, but talk is cheap.

“The Champions League is totally ruthless. Lazio didn’t have many chances the other night, we gave them very little, but they took the ones that came at the big moments.

“We talked last year about learning from our experience, and I honestly think we have, that we’re competing much better than we did then. We’re closer, but we need to show we can make that next step.

“It’s those big moments, they’re what make the difference. At 1-1 the other night, that’s the worst we should be walking away with.

“At 95 minutes we need to be realising the position of the game – of course we want to win it, but we definitely can’t lose it, so to do so is slack on our part.”

Alas, the days since the Lazio defeat have been spent with another swirl of what-could-have-beens circling the heads of the Celtic players, but such introspection is necessary according to Taylor if they are to realise the what-could-be.

“It’s at home that you give yourself a chance of progressing,” he said.

“We’ve got four more group games, two home and two away, so we really need to use the ones here and hopefully make something happen on our travels if we want to be in Europe after Christmas.

“The goal we scored against Lazio shows what we’re capable of. We started the game really well, we controlled Lazio to nothing and we got the goal.

“After we went ahead, we got a little bit ragged, which gave them hope, then we lost a sloppy goal.

“Against top players like these, you don’t want to lose to the kind of set-piece you’ve worked in defending.

“Then in the second half we had pretty much all of the ball. I don’t remember them having anything bar that last chance.”

Taylor will now look forward to some respite from club duty, but the challenge at international level with Scotland isn’t any less daunting.

Steve Clarke’s men will be taking on an away assignment in Spain on European Championship qualifying duty, and then hopping over the border to play out a friendly against World Cup finalists France.

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Having been patiently stalking the immovable pair of captain Andy Robertson and former Celt Kieran Tierney on the left of the Scotland side for years now, an injury to Tierney may open up a chance for Taylor to make his mark for his country. And it is one he is ready to grasp.

“It’s nice to be back involved with Scotland, because it’s always a real honour to represent your country,” he said.

“Hopefully over the two games that lie ahead I can get a run-out.

“The Spain game especially is really big. It’s such an exciting time for the national team and from a personal point of view you only get involved if you’re doing well at club level, which is always where your focus has to be from week to week.

“We’re obviously gutted for Kieran, because it’s really sad news that’s suffered an injury. But it’s part of football and he’ll bounce back. He’s a top professional with a great attitude, so he’ll get his head down and work towards full fitness again.”