What the Champions League quarterfinals taught us

	Even though he's only 18, Cesc Fàbregas has emerged as the driving force behind suprising Arsenal's midfield. Laurence Griffiths/Getty Images
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With the Champions League quarterfinals serving up arguably two upsets out of four, it's time to draw a few conclusions. Here are nine truths I either learned or found reaffirmed:

1. Building a team to win domestic league and Champions League is (nearly) impossible.

Lyon and Juventus went out. Chelsea and Bayern bowed out earlier. Barcelona is the only team that can still do a domestic and Champions League double. It's worth noting that unlike the other four, which are built on defensive and tactical solidity, Barça is built primarily on attacking prowess.

2. Pippo Inzaghi is one of the game's enduring mysteries.

He looks like a gust of wind could carry him away, his technique is good but not great at this level, and he's not particularly quick. Yet the AC Milan forward has that mysterious and indefinable quality: He scores goals. It's the one aspect of a player's game that remains intangible and undefined, beyond the statistics. Logically, he simply should not score so many goals. And yet he does.

3. Gerard Houllier remains one-dimensional.

Against a Milan side that wasn't playing well, Lyon could have gone for the jugular -- and indeed, that might have made all the difference. Instead, Houllier served up the same defend-and-counter approach, which, as we know, will only get you so far in Europe.

4. Barcelona has depth defensively, too.

Those who sniffed an upset brewing against Benfica due to the absences of Carles Puyol (in the first leg), Edmilson and Rafa Márquez were badly mistaken. The often overshadowed Oleguer, Mark van Bommel and Thiago Motta provided the solidity at the back that allowed the front men to do their thing. They deserve credit, too.

5. Ronald Koeman learns from his mistakes.

Some, including yours truly, were not impressed with Koeman while he was with Ajax. I stand corrected. Benfica may be disappointing domestically, but Koeman has that special quality: He's a manager who learns from his mistakes. Against Barça he abandoned the cavalier ways of his past for a more balanced approach that kept the score close. He looks like a coach who will only continue to improve. Let's hope Benfica gives him time to do so.

6. The Juan Sebastián Verón experiment is officially over.

In some ways, he's the anti-Inzaghi. He has everything to be a superstar, which is why so many clubs have been seduced by his ability: endurance, quickness, vision and skill. And yet, he so often fails to produce when it matters. Against Villarreal, Inter needed leadership. He failed to provide it, electing instead to bicker with his opponents, spray balls all over the park and, crucially, lose track of Rodolfo Arruabarrena when Villarreal scored its only goal. Verón should be one of the top 10 players in the world. Instead, he's not even in the top 100. Inter, as a group, was terrible at the Madrigal, so it may seem churlish to single him out. But he's supposed to be the leader.