1. Milan get what they deserve
Milan didn't play like a team that wanted to advance. A draw would've been enough at Olympiacos on Thursday, and at times, it looked as if the Rossoneri would've settled for just that. Their performance was riddled with errors: cheap fouls, numerous corner kicks and set pieces, and horrendous finishing in the final third. Milan again struggled to play for a full 90 minutes, only really kicking into action when they conceded a goal. That can only happen so much without facing the consequences. Milan pulled off comebacks in similar situations over recent weeks, but couldn't find a breakthrough in Athens.
2. Reina proves he's not good enough
Signed as a mentor to Gianluigi Donnarumma, 36-year-old Pepe Reina has hardly looked like a veteran shot-stopper in his short time with Milan. He had little command of his penalty area and often found himself in no man's land. He missed attempts to punch clear and fumbled with the ball outside of the 18-yard box. Reina gave his teammates little confidence on the pitch. It's just not good enough from a player making a reported €3 million a season.
3. Gattuso not the only one to blame
Milan manager Gennaro Gattuso is the easiest person to blame for this fiasco, and there are certainly valid reasons for it. He subbed off Patrick Cutrone when Milan was chasing a goal, but persisted with Hakan Calhanoglu despite clear signs that he's out of form. However, It's not Gattuso's fault that Gonzalo Higuain can't finish his chances. It's not Gattuso's fault that Cristian Zapata's attempt to clear resulted in a fluky own goal. And it's not Gattuso's fault that referee Benoit Bastien awarded a ridiculous penalty to Olympiacos. Gattuso's limitations are clear - he doesn't make the best decisions during matches - but a lot of things that happened on the pitch were out of his control.
4. Castillejo wastes opportunity to shine
Without Suso in the matchday squad, summer signing Samu Castillejo had 90 minutes to show he deserves more playing time. It was disappointing to watch Castillejo spoil that opportunity with clumsy defending and half-hearted challenges. He misread the corner kick that led to Olympiacos' own goal and hardly looked like winning a duel, either on the ground or in the air. It was a weak performance from the winger.
5. Season isn't over yet
The result was humiliating and completely avoidable, but it isn't suddenly the end of the world. Milan now have an opportunity to focus exclusively on Serie A. It would've been great to continue in the Europa League, knowing it could've provided another avenue to the Champions League, but Milan's limited resources can now be put towards a fourth-place finish in the league. And quite honestly, it's a more achievable goal. Anything less will be a colossal failure that could have far-reaching consequences on Financial Fair Play and beyond.