Chelsea’s Champions League future is on the line Wednesday night when the Blues travel to Barcelona to face the Blaugrana at the vaunted Nou Camp.

Few venues in world football are as intimidating as the home of FC Barcelona on a European night, and with nearly 95,000 home supporters in attendance, Chelsea will have to gather all their collective mental strength in order to advance.

The Blues nearly pulled off the perfect performance in the first leg at Stamford. While Barcelona dominated possession throughout the match, it always felt like Chelsea created the better chances on the counter attack throughout the match, most notably through Willian, who scored the lone Chelsea goal and struck the post on two other occasions.

But a mistake from Andreas Christensen led to Lionel Messi scoring the vital away goal, breaking his goalless streak against Chelsea in the process, and, and Barcelona return home on Wednesday with command of this tie.

Many betting sites have Barcelona as favourites at home on Wednesday night, and they’re completely correct. The second-half goal from Messi changed the complexion of the tie, and it means that Chelsea will have to score at least once, and probably twice in order to have a chance of advancing.

It makes Chelsea manager Antonio Conte’s team selection far trickier this time. In the first leg, one thing that helped Chelsea limit Barcelona was the use of Eden Hazard as the lone striker. While it’s not a role that brings the best out of Hazard, it brought the best out of the shape of the team.

At Stamford Bridge, one of the key things that Chelsea did tactically was use Pedro on the left to track Messi during transitional play. One thing that Messi has a tendency to do is work in the centre and right sides of the pitch when he comes deep. He very rarely goes out to the left-hand side of the pitch. Pedro’s job was to stay tight to Messi so that he couldn’t get the ball in transition and then pass him off to the midfield once the team regained defensive shape.

It worked. Messi wasn’t able to find pockets of space with the ball until Chelsea had numbers behind the ball, and without any out-and-out wingers that like to run at defenders to create options, Barcelona had a lot of possession but struggled to create a ton of openings.

That approach isn’t necessarily going to work at the Nou Camp, mostly because Chelsea have to score and can’t simply be content to stop Barcelona from scoring. It may mean that Conte opts for a formation with a recognised striker, especially since the team looks far better in attack when either Alvaro Morata or Olivier Giroud leads the line.

But that will mean that you either lose that tactical discipline defensively on the left, since Hazard isn’t known for his ability to track runners in transition, or you drop Hazard to the bench in favour of Pedro, which would certainly raise some eyebrows.

The one positive for Chelsea is that they now know what to expect from Barcelona. There aren’t a lot of changes that Ernesto Valverde has available to him, so the way that the Blaugrana approached the first leg is likely to be the same way they approach the second leg.

The first leg showed the one weakness that Barcelona has this season, and that’s breaking down sides that sit deep against them and don’t give them space. The one trait that this Barcelona team lacks is quickness.

Outside of Messi, there are very few players in this Barcelona team who will run at defenders with the ball. Ousmane Dembele is one of those players, but injury problems have really halted his development this season, especially since his arrival was supposed to help compensate for the loss of Neymar.

The odds of Chelsea getting the result they need on Wednesday night aren’t great, but if Wednesday’s match start to resemble anything like the first leg at Stamford Bridge, Chelsea’s hope and confidence may start to grow, and it could make for an entertaining spectacle.