Youthful exuberance has already taken Chelsea further than many anticipated but Tammy Abraham must help add a clinical touch to keep their Champions League campaign on track.

“Moments in the boxes” is how Frank Lampard described the decisive factor in Saturday’s 2-1 defeat at Manchester City, adding the salient point that polished teams get the “finer details” right on a regular basis.

It is a testament to the work Lampard is doing that Chelsea are succumbing by such small margins to the top sides, yet their hopes of challenging for honours this season will depend on efficiency under pressure.

Their first meeting with Valencia remains a poignant example, contributing to a defeat which Lampard still rues now as the one which put them on the back foot in Group H. 

Valencia edged a tight contest by a solitary goal in September as the Blues erred at the back and faltered at the front, with Ross Barkley missing a late penalty to earn a point which would give the table an entirely different complexion now.

Barkley misses this trip altogether as he continues to recover from both an ankle injury and the embarrassment of provoking his manager’s ire at again being pictured in a questionable condition during a night out, so the responsibility falls elsewhere to deliver the result they badly need.

Abraham has enjoyed an excellent season to date – 10 goals puts him second in the Premier League scoring charts, while he got off the mark in this competition at Lille and also registered his first senior international goal during England’s 7-0 thrashing of Montenegro earlier this month.

The 22-year-old is improving and may well become an elite-level striker to rival the very best, but to do so those nagging doubts about his finishing against the toughest defences must be silenced.

Lampard has had little cause to be defensive about anything this season but he verged on the dismissive when rejecting the notion Abraham had such a case to answer.

“If you want to talk about Lille away in a difficult Champions League game, then that’s a big game for me,” he said. “If you want to talk about every game in the Premier League, then that’s a big game for me.

”If you want to classify the top six in the Premier League then who are the top six? From week to week it changes. So Tammy scored a big number of goals. There’s absolutely no fear to that.”

Yet, a closer look at Abraham’s performances suggest otherwise. Five of his 10 League goals have come against teams in the bottom half, four of them against teams currently comprising the bottom three.

In seven games against Liverpool, Leicester, City, Ajax and Valencia, Abraham has failed to score.

And these are precisely the matches Lampard describes as being settled by “moments in boxes”, even if it does sound like a saccharine promotional tagline for a Christmas giftware range.

“At Manchester City, you are talking about a particularly high-level game with two teams going at each other,” he said. “So the moments in the box are always going to be the things that count in those games. 

“Every game in the Champions League pretty much at this level can be decided in this way. It can be the battle in midfield. It can be tight and difficult but you have to be clinical in both boxes.

”That’s a rule in football but particularly when there is so much at stake. When the opposition or the match is tight.”

Abraham will not shy away from the responsibility, opting to speak at the pre-match press conference when it would have been easier to hide, and claiming he has spent time watching YouTube videos of Harry Kane, Sergio Aguero and Roberto Firmino to hone his craft.

This, by his own admission, is “the biggest game of my career” and that will be the same for several others, particularly Fikayo Tomori in the other box. Lampard knows they must get it right.

Valencia are 12th in La Liga and were outclassed by Ajax in contrast to Chelsea’s resilient displays in their two clashes with last season’s semi-finalists. 

But they are a more experienced group who proved in west London they can be savvy on the big occasion. Chelsea’s young guns will need to show the same.