Image source, Getty Images

Atletico Madrid flew out of the blocks in Wednesday's first leg with Rodrigo de Paul scoring after just four minutes before Samuel Lino doubled the lead after half an hour.

With Madrid looking to put the tie beyond Borussia Dortmund, substitute Sebastien Haller struck to give the German side hope.

Julian Brandt almost stunned the Wanda Metropolitano after his header bounced off the woodwork in the final stages of the game.

We could have a classic on our hands tonight.

Barcelona boss Xavi makes just one change to the side that beat Paris St-Germain last week in the first leg.

Midfielder Sergi Roberto makes way for 21-year-old Pedri, who made an instant impact when he came on as a substitute in last week's first leg, setting up the second goal.

Andreas Christensen, who scored the winner at the Parc des Princes, is suspended after picking up a third yellow card in the same match.

Teenagers Lamine Yamal and Pau Cubarsi retain their places.

Barcelona XI: Ter Stegen, Kounde, Araujo, Cubarsi, Cancelo, Gundogan, Pedri, De Jong, Raphinha, Lewandowski, Yamal.

Subs: Martinez, Torres, Pena, Felix, Alonso, Romeu, Vitor Roque, Astralaga, Casado, Fermin, Guiu, Fort.

Paris St-Germain boss Luis Enrique makes three changes to the side that narrowly lost the first leg.

In comes Achraf Hakimi after he was suspended for the first leg.

Bradley Barcola also starts in place of Marco Asensio while Warren Zaire-Emery's inclusion means it is the first time three players under the age of 18 have started a Champions League knockout stage match, along with two Barcelona youngsters.

Lee Kang-in and Lucas Beraldo drop to the bench.

Paris St-Germain XI: Donnarumma, Mendes, Hernandez, Marquinhos, Hakimi, Ruiz, Vitinha, Zaire-Emery, Dembele, Mbappe, Barcola.

Subs: Navas, Ugarte, Ramos, Asensio, Pereira, Lee, Kolo Muani, Mukiele, Soler, Beraldo, Tenas, Skriniar.

Things are building up nicely in Dortmund and Barcelona.

Image source, Getty Images

Image source, Getty Images

Borussia Dortmund make one change from the first leg as Julian Brandt comes in for Felix Nmecha who drops to the bench.

Manchester United loanee Jadon Sancho keeps his place, but striker Sebastien Haller, who scored in the first leg, is out with an ankle injury.

Borussia Dortmund XI: Kobel; Ryerson, Hummels, Schlotterbeck, Maatsen; Sabitzer, Can; Sancho, Brandt, Adeyemi; Fullkrug.

Subs: Meyer, Lotka, Salih Ozcan, Nmecha, Reus, Duranville, Wolf, Moukoko, Sule, Watjen, Bynoe-Gittens.

As for Atletico Madrid, they also make one change with suspended midfielder Samuel Lino replaced by defender Mario Hermoso.

Saul Niguez, who was a doubt, makes the bench, but Memphis Depay is not fit enough to be in the squad.

Atletico Madrid XI: Oblak; Witsel, Gimenez, Hermoso; Molina, Llorente, Koke, De Paul, Azpilicueta; Morata, Griezmann.

Subs: Moldovan, Gomis, Gabriel, Saul Niguez, Correa, Savic, Riquelme, Vermeeren, Reinildo, Barrios, Nino.

Barcelona v Paris St-Germain (agg: 3-2)

Borussia Dortmund v Atletico Madrid (agg: 1-2)

Both games kick-off at 20:00 BST.

Image source, Getty Images

Four teams, two places up for grabs in the Champions League semi-finals and that means two teams are leaving the competition tonight.

The first legs delivered as Barcelona came from behind in France to beat Paris St-Germain 3-2, while Atletico Madrid held off Borussia Dortmund to win 2-1 at home.

Both ties remain finely poised but there has to be two winners tonight. Who will it be?