Two more Champions League games to play today, so let’s get right to it.
Napoli vs Barcelona
Not all struggles are created equal. Barcelona are having a difficult season. They’ve changed managers, their major attacking signing, Antoine Griezmann, has failed to settle, their attacking play looks staid and boring. Things just aren’t going nearly as well as they could be at Camp Nou. Yet they’re also leading La Liga with 55 points, two ahead of Real Madrid. They’ve got the best expected goal total per match in Spain at 1.68 and the third-best xG conceded total at 0.79. So, like, there’s bad for Barcelona, and there’s actual bad, and this season clearly falls into the first category, not the second. Barcelona are the ultimate rates and levels team. The level of their play has been so high for so long, because Lionel Messi is a supernatural artifact bestowed upon us by technologically advanced soccer-loving aliens, that any drop in form seems like the end of the world. But really, they’re still a very very good team. New manager Quique Setien has helped steady the ship. And while he’s brought a somewhat unadventurous possession style to the team, the side's attacking play immediately improved, without much in the way of increased defensive problems. 
Barcelona’s main issue is still that everything runs through Messi. Five years ago their main problem was that everything ran through Messi, and the situation has only gotten more extreme since then. With Luis Suárez out, his combined goals and assists per 90 minutes are almost double anybody else’s on the team. 
You’d be tempted to say it’s unsustainable, but, well, it’s Messi. Napoli’s situation is a little more complicated. On the one hand, they’re in sixth place with a goal difference of exactly four. That’s quite the drop for a team that spent years trailing only Juventus in Serie A. On the other hand, their xG difference of 0.55 is the fourth-best in the league and paints them in a considerably better light than their record and place in the table does. Put it all together and you have a Napoli team that is definitely worsening in comparison to seasons past, but not nearly as quickly as their drop down the table suggests. Specifically, from last year to this year the defense has eroded and they've gained little attacking input to compensate. 
Nothing much has changed under new management. Carlo Ancelotti and his flexible 4-4-2 might have departed for Everton and been replaced by Gennaro Gattuso and a more traditional 4-3-3, but the basic contours of the problem remain exactly the same. Napoli are a pretty good side, but they aren’t as good as they used to be, and they certainly aren’t getting any better. Despite their struggles Barcelona are a significantly better side. When you’re a team that’s getting slowly worse it sure helps to have Lionel Messi.
Chelsea v Bayern Munich
Two months ago a matchup between Chelsea and Bayern Munich might have looked like an opportunity for the English side to pull off a surprising upset. Bayern were in the midst of firing their manager while Chelsea were flying high off surprisingly strong performances from the youth movement who'd finally been given a chance. Then injuries hit Chelsea, Bayern righted the ship and now the task looks monumental for Frank Lampard’s men. Chelsea’s attack has tapered off dramatically. With Christian Pulisic out injured and Tammy Abraham injured, but not quite out, the side’s xG has really come back to earth since the turn of the year. 
But, despite the attacking struggles, it’s really defensively where the Blues are likely to get exposed against Bayern. Chelsea are a very aggressive defensive side. They don’t know how to sit back and instead want to press from the front and defend in their opponent’s half. At their best they create opportunities for their attacking trio by winning the ball high up the pitch. At their worst they end up playing destabilized football, exposing themselves to opponents who are disciplined enough to hold the ball against them. 
Bayern are clearly disciplined enough. The side's high-powered midfield often features Joshua Kimmich at the base, and he’s simply a machine at moving the ball up the field without losing possession. 
The same is true of Thiago, who both advances the ball from deep and moves forward to help orchestrate the attack. 
It’s possible that a disciplined underdog might cause Bayern problems. Their attacking front line is great, and Robert Lewandowski continues to have an all-timer of a season, smashing goals from the best spots in the world. 
But, maybe under the right circumstances, with a little bit of luck and a lot of deep defending an underdog could hold them and exploit the German giants on the counterattack. Chelsea under Lampard simply don’t have that club in their bag. In order to win they’re going to need Bayern’s midfield to crack under the pressure they apply. That seems exceedingly unlikely to happen.