Napoli won the first leg with a convincing 3-1 win in Italy. Now, the tie moves to London, where Chelsea will hope to reverse their fortune. With Andre Villas-Boas gone, Chelsea have seemingly gone back to the old guard, but they haven't looked much better.
With English teams failing in European competitions, Chelsea have a lot of outside pressure to play well on Wednesday.
Chelsea are definitely capable of winning, but they need to make up the goal differential, without conceding too many away goals.
Meanwhile, Napoli are looking to knock off another English giant in England. They have put themselves up two goals on aggregate and a decent showing should help them advance.
Chelsea will be playing desperate. If they want to come back, they must play very well. In order to ward off Chelsea's siege, Napoli must play well in a different country.
Here are the tactical keys for each side.
Chelsea attacked relatively well against Napoli in the first leg.
They moved the ball pretty well in the midfield and countered quickly. However, once the ball got in the attacking third, Chelsea lost their aggression. Suddenly, Chelsea lost any and all creativity to break down the final line of Napoli's defense.
If Chelsea want to score multiple goals against Napoli, they need to play direct and play the ball wide. When the Blues get width, they can open up their opponents, resulting in quality chances for the attackers.
If the Blues try to drive the ball through the middle of Napoli's defense, they will have a very tough time penetrating the Italians.
Napoli have one of the best attacking trios in the the world.
Edinson Cavani, Marek Hamsik and Ezequiel Lavezzi will be giving Chelsea's defense fits all night. They were finding open space for the entire first leg, but it might not be as easy this time around.
Chelsea are more desperate, and they will have a different defensive scheme in place.
Regardless, Napoli need to play quickly. Chelsea are prone to mistakes, so Napoli must play directly into the defense. Hamsik and Lavezzi are nightmares for defenders while dribbling the ball. Meanwhile, Cavani is one of the strongest, surest finishers in the world.
Counterattacks and direct attacks will be Napoli's best chances for goals. Petr Cech will be a tough final line of defense, but Napoli have already scored three goals on him so they definitely won't be intimidated.
Napoli are fast and dangerous; they just need to play like it.
Chelsea's biggest issue with defending is organization.
The defense as a whole has had a tough season to say the least. The players aren't playing poorly on an individual level. However, at least three or four times in a match (12 or 13 times against good teams), there is a semi-major meltdown.
That can't happen against Napoli.
The defenders must maintain a strong line because Edinson Cavani (as well as anyone else on the Napoli front line) has the ability to finish once he's behind the defense. It doesn't matter who makes up the back four; they, along with Petr Cech, must play a great game for Chelsea to have a chance.
Chelsea's defense was porous in the last match against Napoli, and Cavani could've easily netted a hat trick. Cech came up big multiple times, but the defense can't expect him to put in another spectacular performance.
In order to negate Napoli's great attack, Chelsea must avoid cheap turnovers in the midfield and tackle well. If Chelsea allow Napoli quick counterattacks off turnovers, the Napoli forwards will tear apart the defense (or any defense, for that matter).
As Napoli are building the attack, Chelsea must execute their tackles well. Missed and/or halfhearted tackles will give Napoli the space they need.
If Chelsea avoid lazy turnovers and bad tackles, they should be able to keep the Napoli attackers in front of them. From there, they stand a much better chance of holding a clean sheet.
The best thing Napoli can do defensively is pinch Chelsea.
The Blues are effective when they split wide, but they prefer to attack through the middle. Napoli should encourage Chelsea to attack through the middle because their defense is too good to break through the middle.
Napoli should focus on keeping a clean sheet for at least the first 45 minutes. Chelsea need at least two goals, which means they will be pressing from the start.
If Chelsea don't score in the first half, they are going to pile on an intense attack. Napoli's defenders must remain organized and distribute the ball quickly. If they can facilitate the counter, Napoli become devastating.
Napoli's defense must stay diligent and focused, even if England is a tough place to come in and play well. They did it in their first Champions League match this year so they're definitely capable of doing it again.
Chelsea can't afford to be too reckless right out of the gate.
Yes, they need at least two goals, but Napoli's counterattack is devastating. If Chelsea push too far forward too quickly, they may find themselves with an insurmountable deficit.
Chelsea must play with a patient urgency. It sounds a little contradictory, but it's the truth. The players must understand the stakes, and they need to play with urgency. However, they shouldn't force anything and play too aggressively too soon.
The Blues need to get a feel for the game and slowly start piling on a stronger attack. A first-half goal is ideal, but it isn't necessary.
If Chelsea are attack-minded but patient, they will have a very good chance of winning this tie at Stamford Bridge.
Napoli can't be too defensive too early.
If Napoli try to pack in their defense for 90 minutes, they will surely lose by multiple goals. However, if they play Chelsea straight up with a defensive mindset, they stand a very good chance of winning the tie.
Napoli don't need to win the match. They don't need to score goals. If Walter Mazzarri's side can hold Chelsea to a single goal, they could lose the match but still win with an aggregate score of 3-2.
Napoli also can't afford to be too offensive. They need a few midfielders to hang back on some attacks in order to prevent a quick Chelsea counter. If Napoli play Chelsea straight up, they could win on talent alone.
As a Chelsea fan, I hope Mazzarri tries to hold out with a commitment to defense. However, as a football fan, I know that he's too smart to just let Chelsea attack. He will play Chelsea straight up, and he will give his Napoli squad the best chance to win.
I think Chelsea will win the match. I think the Blues have turned a corner, and they are a different team than the one that visited Napoli on Feb. 21. They will get the ball wide and score a few goals.
However, Napoli's attack is too good to hold under wraps. It would be great to hold them to a clean sheet, but that is extremely unlikely. Napoli have multiple players that could end up with a hat trick before 90 minutes are up.
Chelsea's defense simply can't match up with them, and they will not be able to hold them to fewer than two goals. Additionally, Chelsea won't be able to overcome that suspect defense by scoring five goals.
This game will be close, and both teams will do what they have to do to win. However, Napoli will make fewer mistakes, which will bode well for them.
Chelsea should win this match at home, but they will lose the tie on aggregate. A 3-1 deficit is a tough scoreline to overcome, which is why I'm predicting Napoli to win the tie.