Barca come into the match with an away-goals advantage courtesy of the 1-1 draw in the first leg at Stamford Bridge last month, and they have lost just one of their last 47 matches in front of their own fans across all competitions.
Chelsea are unbeaten in their last eight meetings with the Spanish giants, though, and their last visit to this stadium saw them claim a famous 2-2 draw which took them through to the 2012 final.
Make sure you don't miss a moment of the action courtesy of our minute-by-minute updates below.
BARCELONA: Ter Stegen; Roberto, Umtiti, Pique, Alba; Rakitic, Busquets, Iniesta; Dembele, Suarez, Messi
BARCELONA SUBS: Cillessen, Paulinho, Alcacer, Digne, Gomes, Vidal, Vermaelen
CHELSEA: Courtois; Azpilicueta, Christensen, Rudiger; Moses, Kante, Fabregas, Alonso; Hazard, Giroud, Willian
CHELSEA SUBS: Caballero, Morata, Pedro, Bakayoko, Zappacosta, Cahill, Emerson
20 min What a way to get your first ever Barcelona goal! Dembele opens his account with Barca's second goal of the night, and it comes at the end of a devastating counter-attack, with Messi again the inspiration.
The Argentine steals possession from Fabregas on the halfway line before getting his tow to the ball just in front of Christensen and Azpilicueta to send him down the left. He then takes his time and knocks a square ball across the box for Dembele, who takes his time before hammering a brilliant finish into the top corner.
20 min GOAL! Barcelona 2-0 Chelsea (Ousmane Dembele)
18 min Barcelona have slowly begun to sap the fightback out of Chelsea here, taking control of possession and just knocking it about themselves. They are happy to slow the tempo of the game right down.
16 min Chelsea certainly haven't let their heads drop after falling behind so early. They look very up for this one, hounding Barcelona to win the ball back and then looking to get forward quickly.
14 min Here is that Messi opener - a stroke of luck, a goalkeeping error and a 99th Champions League goal for the maestro.
12 min SAVE! Ter Stegen is called into action for the first time tonight as Willian drills a low strike towards the bottom corner, but the Barcelona keeper gets down well to make the save and crucially holds on to it too.
11 min Chelsea will certainly be encouraged with their response to that early goal. Since Messi snuck the ball between the legs of Courtois Chelsea have looked much the more likely to add the game's second goal.
9 min This has been a really good response from Chelsea to falling behind, and they almost get in down the right flank here until Iniesta stops the move with an inch-perfect sliding challenge inside his own area.
8 min It is a new record for Messi! And an extension of his incredible record against English opposition too...
6 min Chelsea look for a quick response as Willian whips a free kick in towards the near post which takes a deflection off a Barcelona man on the way through before going into the side-netting.
5 min That goal is a huge blow for Chelsea, of course, but it doesn't really change their task tonight. They knew they needed to score here, and that is still the case.
3 min Oh it is a nightmare start for Chelsea as Lionel Messi makes it two goals against Chelsea - and it has taken only three minutes of the second leg!
Messi often makes goalkeepers look stupid, but Courtois really should do a lot better here. Barca get a stroke of luck on the way through as Messi's first attempt at a one-two is blocked, but falls kindly for Suarez, who then plays Messi in down the right channel. It looks like an impossible angle, but Messi sneaks it through the legs of Courtois, who simply has to save it from there.
3 min GOAL! Barcelona 1-0 Chelsea (Lionel Messi)
1 min KICKOFF: Here we go, then! Who will become the final name in the hat for the quarter-finals? Barcelona get us underway at the Camp Nou!