Arsenal vs. Olympiacos: 5 Things Learned About Gunners' Champions League Hopes

So, then, are we happy? Angry? Or do we even care?

For Arsenal fans, Tuesday's 3-1 defeat at Olympiacos feels like one of those losses that means nothing but still makes you uneasy. That is, of course, if you even care.

Arsenal had already qualified for the final 16 of the Champions League, and nothing that happened Tuesday could change that. Likewise, Arsenal had already guaranteed itself first place in Group F no matter what happened.

So why do I feel a little unsure about this team's chances?

Regardless of Tuesday's result, we should all give Arsenal credit for successfully navigating what was actually a pretty tough group that also included German champions Borussia Dortmund (who finished in last place!) and Olympique Marseille.

But at the same time, Arsenal's defense turned in a shocking performance against Olympiacos on Tuesday. And as for the goalkeepers (yes, plural), well, they were even worse.

Granted, this was a mostly second-string Arsenal team. So it wouldn't be right to freak out too much. But while these weren't the first-choice players, a number of them would be among the first three off the bench in a more competitive match.

If that's enough enough to scare you, how about this: Even though Arsenal won their group, they could still face AC Milan in the round of 16.

If that happens, the defense will have to be a lot better than it was Tuesday.

Cross your fingers…

1. Szczesny Must Stay Healthy

If Arsenal want to make a deep run in the Champions League, Arsene Wenger can't choose Lukasz Fabianski or Vito Mannone again.

In a word, both of Arsenal's backup keepers were crap.

Fabianski lasted all of 25 minutes before being substituted. He had to go off after a collision with teammate Thomas Vermaelen, but not before he conceded a soft opener.

True, the opening goal wasn't really Fabianski's fault. But he didn't exactly cut an imposing figure while he was on the pitch, and his feeble attempt to spare Arsenal's blushes after that first costly defensive mixup was laughable.

Once again, Flapianski showed he's just not good enough to play for Arsenal.

As for Mannone, the less said the better.

The third-choice keeper refused to hold any shot that came his way. He couldn't distribute. He looked extremely uncomfortable.

And, incredibly, he gave Marouane Chamakh a run for his money as the least talented Arsenal player on the pitch.

2. Djourou and Squillaci Must Stay Away

Sebastien Squillaci and Johan Djourou played decently against Manchester City last week in the Carling Cup. But they were shocking against Olympiacos on Tuesday.

True, the entire defense had a bad game, but Djourou and Squillaci were especially poor.

Djourou nearly got his keeper seriously injured after a sloppy back pass invited an Olympiacos attacker to make a blue-blooded challenge on Vito Mannone. And that wasn't the only incident: Djourou was sloppy and careless throughout.

Squillaci, for his part, kept backing off Olympiacos' attackers, no more so than on a break late in the second half. Perhaps he thought defenders are more effective when they mark the penalty spot instead of the late runner.

Note to Arsene Wenger: Avoid playing either of these guys again unless it's absolutely necessary.

3. Same for Arshavin

Andrei Arshavin has been in decline for several months, and at this point, it's getting sad.

With his disinterested, low-energy performance Tuesday, Arshavin once again showed he's just not up for it.

And that's not just in Europe. He's done.

Sell him already.

4. Frimpong, Coquelin and Oxlade-Chamberlain Can Help

For all the negativity Tuesday night spawned, Arsenal produced a few positives.

The Gunners' outstanding young trio of Emmanuel Frimpong, Francis Coquelin and Alex Oxlade-Chamberlain once again played well.

They weren't brilliant, mind you. At times they looked overwhelmed, and none of them reached the heights they hit last week against Manchester City.

But they all acquitted themselves well enough to justify selections in Arsene Wenger's squads later on in the Champions League. Frimpong was the pick of the three Tuesday with his bruising (if at times out of control) performance in the holding midfield role.

At this point, it's difficult to see why Wenger would pick Arshavin ahead of any of them.

5. Actually, We Didn't Learn Anything

On second thought, we didn't learn much Tuesday.

Arsenal's starting 11 against Olympiacos included a grand total of two regular starters—defenders Andre Santos and Thomas Vermaelen.

The rest were either bit-part players, substitutes or scrubs.

Robin van Persie was nowhere to be found. Neither were first-choice goalkeeper Wojciech Szczesny, central defenders Per Mertesacker and Laurent Koscielny or midfielders Mikel Arteta, Gervinho and Theo Walcott.

What does that mean?

That means Arsenal played its B-team in Greece on Tuesday. That's not the team we'll see the rest of the season in the Champions League.

Let's just hope the first-stringers didn't pick up any of their backups' bad habits.