Champions League: Barcelona v Tottenham
Date: 11 December Kick-off: 20:00 GMT Venue: Nou Camp
Live text on the BBC website and commentary on BBC Radio 5 live

Guillem Balague will be writing a regular column throughout the season and also appearing every Thursday on BBC Radio 5 live’s Football Daily podcast, when the focus will be on European football.

You can download the latest Football Daily podcast here.

Tottenham travel to the fearsome environs of Barcelona’s Nou Camp on Tuesday knowing they are probably going to need a win if they are to progress to the knockout stages of the Champions League.

Barcelona are top of La Liga, qualified for the Champions League last 16 with a game to spare and are already confirmed as Group B winners.

Tottenham go into the match in second place, above Inter Milan courtesy of a superior head-to-head record, yet they are outsiders to advance. Inter host bottom side PSV Eindhoven and Spurs know they must at least match Inter’s result. It is in their own hands, yet it is a tall order.

But while a trip to face Lionel Messi and co on their home turf may be about as daunting a task as there is in European football, Tottenham have a fair chance of upsetting the odds because there are a few issues facing Barcelona at the moment.

Questions persist about manager, style and defence

Barcelona are three points clear at the top of the table, have won the Spanish Super Cup, demolished Real Madrid 5-1, and have strolled into the knockout stages of the Champions League.

But despite that, doubts remain from commentators and, reportedly, even directors about some of manager Ernesto Valverde’s decisions.

The Spaniard navigated a difficult start to his tenure in 2017 – the loss of Neymar to Paris St-Germain was followed by a humiliating Spanish Super Cup defeat by Real Madrid – and emerged with his side league and cup double winners.

But Valverde is finding himself at the centre of the perennial substance-versus-style argument that always rages in Barcelona, a club where the mere act of winning is only ever a sub-plot to how the victory is actually achieved.

The feeling from many – both inside and outside of the club – is that there is too much box-to-box football, with too few passes being made, not enough control. Plus too much dependence on Messi, as if anything else was possible. Some suggest Valverde is not brave enough as a coach.

Recently, his demeanour in press conferences – the tension on his face evident – suggests he cannot believe some of the questions he is being asked.

‘What else do they want?’ he seems to be asking. And it is a fair question. He is going through the tough period of a post-Xavi and Andres Iniesta transition while winning in the process. Sometimes it feels the shadow of Pep Guardiola – or the memory of a side that broke all kinds of records while playing wonderfully – still looms large.

They certainly have their fair share of problems, particularly in defence. They defend crosses from the wings poorly and they are not strong, determined or efficient enough defending in their own box.

They have already conceded 19 goals in 15 league games – only seven teams in the division have let in more.

Clean sheets against Espanyol on Saturday and Villarreal on 2 December were their first since 26 August, when they won 1-0 at Real Valladolid in their second game of the season. Had they conceded against Villarreal it would have equalled their longest run without keeping their opponents out since 1998.

The Dembele dilemma

In £135.5m forward Ousmane Dembele, Valverde has a wonderful talent but also a young man with an apparent discipline deficiency.

The former Dortmund attacker has gone “missing” from training, with Barcelona having to send a doctor on an hour-and-a-half journey to meet him after he “forgot” to tell the club why he was absent. And last week he arrived two hours late for training and had to work on his own as he was “confused” about what time it started.

Fed from the inside, stories of the mess in his living accommodation, the unhelpful friends that surround him, the excessive hours playing computer games and the Frenchman’s inability or lack of enthusiasm for learning the language have ended up in the papers.

Dembele has no doubts about his own abilities – as demonstrated by a beautiful curling goal in Saturday’s 4-0 thrashing of Espanyol – but he has not really settled as a team player on or off the pitch, although Valverde and, on Sunday, even Messi, have been doing their best to protect him.

The 21-year-old feels he has not received the respect he is entitled to and expects his talents as a fine player to be acknowledged by everyone, not least his peers.

But he is forgetting that in the demanding environment that is the Barcelona first-team squad, being a very fine player is merely the minimum requirement. He needs to learn that respect is earned, not donated.

In mitigation, however, he is young and unlike his 22-year-old Brazilian team-mate Arthur Melo, Dembele does not have the protective shield of his family around him to help give him some perspective. Barcelona have tried to convince his agent to move to Barcelona to look after his welfare, but to no avail.

Philippe Coutinho’s failure to make a major impact has not helped to alleviate the focus on Dembele. The Brazilian has been troubled by injuries but the former Liverpool attacker has not been affecting games as much as he should have. Barcelona have only enjoyed moments of brilliance among many minutes of anonymity. Much more is expected.

The Messi factor

According to the Ballon d’Or, Lionel Messi is the fifth best player in the world, which brings to mind a quote from Private Eye editor Ian Hislop, who once stood on the steps of the High Court following a libel decision to proclaim: “If that’s justice, then I’m a banana.”

Messi’s 50 appearances, 45 goals, 23 assists and four hat-tricks deserved at least a top-three finish.

He is now, with the departure of other senior leaders in the side like Xavi, Iniesta, and Carles Puyol, effectively the only real captain in the dressing room.

He is also the only player who has it in him to be the one – as they say in Spain – “to pick the chestnuts out of the embers”. He is Barcelona and football’s Superman, the club’s perennial “get out of jail free” card.

More mature and talkative, protective of the new acquisitions and arrivals, he now plays in a more changeable role – against Atletico Madrid he operated behind Suarez and alongside Vidal, but he can be seen deeper, on the right wing or as a number nine, more a passer than a finisher compared to previous years, but still scoring the usual high number of goals wherever he goes. His understanding and relationship with Jordi Alba and Luis Suarez continues to be a focal point of the Barcelona gameplan.

Valverde, with whom he has a great relationship, is not the first and almost certainly will not be the last manager to work to a plan that involves giving him the ball as much as possible.

It remains to be seen whether Messi will play in a game that means nothing to Barcelona, but if he does, Spurs might really have a problem since this season his eyes are very much focused on what he has already described as that “copa tan linda” – that “most beautiful cup” – that is the Champions League.

And let’s not forget he produced a masterpiece of a performance at Wembley two months ago, scoring twice to swing the game decisively towards Barca. He wants to take his team to new heights, so he is happy they all take his lead.