1. Was zonal marking to blame for Celtic’s loss last night?

Celtic’s concession of two sloppy goals from set pieces last night led some critics to suggest that their zonal-marking policy was consequently to blame for the 3-0 loss to Milan.

Yet such criticisms seem lazy and reactionary — it’s rarely asked if teams would have benefited from zonal marking in instances where goals are conceded from corners against defences adopting the more traditional man-to-man-marking policy.

However, whenever a team who employ zonal marking concede, the system rather than the players are blamed.

Like any tactical strategy, zonal marking is imperfect, but to dismiss it so readily seems a little naive — especially as many of the best managers in Europe, including Rafa Benitez and Arsene Wenger, employ it on a regular basis with relative success.

2. When it comes to PR, few managers are as adept as Jose Mourinho

It’s no accident that Jose Mourinho appears invariably loved by the majority of his players. Following a sluggish Chelsea performance in which they were deservedly beaten 1-0 by Swiss side Base yesterday, Mourinho said: “It is not the kind of game where we are upset with the players, because I think I understood, and I maybe should have made more changes.”

So essentially, not for the first time, he took the blame for the loss.

The Portuguese coach is in a strong position — he is so loved by the fans for his past achievements that they are unlikely to start a backlash against him any time soon in spite of the occasional perceived ‘mistakes’ that he makes.

Therefore, while his team obviously weren’t good enough on the night, he has little to lose by astutely focusing on his own failings rather those of his players.

3.  Statistics mask Barcelona’s flaws

(Barcelona’s Neymar, second right, challenges Ajax’s Stefano Denswil, first right, during the Group H Champions League soccer match — Patrick Post/AP/Press Association Images)

Ajax pulled off the surprise of the night as they beat Barcelona 2-1 in Amsterdam.

The result brought an end to the Spanish side’s 20-match unbeaten run and can be partially explained by the absence of key players.

Yet their display in last night’s game was the latest instance of a consistent trend whereby Barca have palpably underperformed in Europe, despite finding themselves in an average enough group.

Their failure to beat a troubled Milan side and their somewhat fortuitous defeat of Celtic were two further suggestions that they aren’t anywhere near the level reached by past incarnations of the team.

4. Arsenal look like genuine Champions League dark horses

The ease with which Arsenal overcame Marseille last night was a sight to behold. They secured a comfortable 2-0 home victory and could even afford a Mesut Ozil missed penalty along the way.

The Gunners’ qualification was all but confirmed as a result — barring a loss of three goals or more in their final fixture away to Napoli, they are assured a place in the last 16.

Moreover, out of all the English teams, their group was surely the toughest, hence the achievement is particularly impressive.

As they look set to qualify above Borussia Dortmund — last year’s finalists — they now surely have to be considered as genuine contenders to lift the trophy.

That said, they have at times lacked the conviction they exhibit at their fluent best against the top sides — their 1-0 loss away to United in the Premier League being a prime example of this sporadic flaw.

So while they undoubtedly have the talent to triumph, they are rightly considered far from favourites to do so.

5. Lennon doesn’t seem to fully trust Stokes

Earlier this season, Anthony Stokes appeared to be in the form of his career.

He played an integral role in Celtic’s early successful Champions League games and the Irish international was rewarded with a new contract as a result, thereby suggesting Lennon had finally fully embraced Stokes as a player.

However, just as he consistently tended to do in the striker’s younger days, Lennon dropped him on the big occasion against Milan last night, opting instead to play the goal-shy Greek Georgios Samaras in the lone frontman role.

Accordingly, the 25-year-old star must now be wondering if he’ll ever be able to earn the full trust of his manager.

As it happened: All of tonight’s Champions League action>

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