Aubameyang lissabon
But Benfica are a long-beaten team now, they have had barely any possession in the second half. Pizzi is penalised in the centre circle for a trip on Castro, playing in place of the injured Reus tonight.
Andrija Zivkovic replaces Samaris, the Serbian coming on to make his first appearance in the Champions League.
Dembele down again as Luisao makes contact with his knee. He made the most of that, really. Dembele is pulled back by Samaris, who is already on a yellow card.
Martin Atkinson comes across to have a word with the Greek. Mitroglu wins a foul in the centre of the field, and Dortmund head clear the corner under pressure from Luisao.
Aubameyang is flying now, he gets down the right flank and pulls the ball back but Castro shanks his volley wide. Nothing Ederson could do about that.
Pizzi crosses a free-kick towards Luisao, and Piszczek heads out for a corner. Almeida gives away a foul for a silly trip on Pulisic, after Luisao had made a good challenge on Dembele.
Dortmund kick off the second half in the Westfalenstadion - it is on aggregate, and we could be going to extra-time if it stays like this.
One minute of additional time. Dortmund lead , and it is on aggregate at half-time. Schmelzer crosses from the left and Lindelof clears.
Aubameyang feels Eliseu clips his heels in the box and looks hopefully for a penalty. Piszczek fouls Cervi down the left and Benfica have a chance to swing the ball into the Dortmund box.
Dembele is late on Eliseu, and the Benfica bench is up and furious, as they feel Martin Atkinson should have shown a second yellow card.
Tuchel, wearing one of those puffy black jackets that no Englishman would dare wear, extravagently encourages his players from the touchline.
Semedo chips the ball up towards Mitroglu, but, though the clearance is poor from Dortmund, Salvio overhits the follow-up cross.
Samaris pulls down Dembele and gets a yellow card, which will see him miss the first leg of the quarter final should Benfica progress.
Castro jumps in on Almeida and gets a yellow card. That was a two-footed challenge, so could actually have been a red card. Eliseu does well hold off Durm down the Benfica left and the defender wins the free-kick as English lineman Stuart Burt flags.
Lots and lots of Dortmund pressure now, Semedo heads clear a diagonal ball towards Schmelzer and Benfica can clear. Semedo tries a run down the right but Bartra nicks the ball and then waits for the push in the back by Semedo to get the free-kick.
Benfica clear the free-kick, but Salvio is bundled off the ball as he tries to attack down the left. Samaris hacks down Dembele near the centre circle.
Referee Martin Atkinson has a word with the Greek. Ederson is out to head clear from Aubameyang from yet another long ball down the middle.
Durm then tries an optimistic effort which sails over the bar. Pulisic takes on Luisao down the right, but there is no yellow shirt on the edge of the box and Samaris can clear his pull back from the touchline.
Another corner for Dortmund down the right. Schmelzer gets the ball down the left, but Lindelof does well to clear the angled ball towards Aubameyang.
Dortmund counter at pace, but Dembele cuts in on his right foot and shoots well over, with Aubameyang waiting. Mitroglu holds the ball up, Pizzi swings in a ball from the left which Schmelzer is forced to head out for a corner.
But Dortmund clear, though some Benfica players are looking hopefully at the referee for a possible handball. Dembele runs at the Benfica defence but makes a mess of his options, with Perisic and Aubameyang waiting, and the ball runs out for a goal-kick.
Demebele wins the second corner of the game following a lightning quick run down the left, the ball deflecting off Semedo. Lindelof heads clear a ball through the centre towards Aubameyang, and Benfica can bring the ball out.
Samaris fouls Pulisic near the centre circle, Luisao is able to stab the ball from the free-kick out for a corner under pressure from Aubameyang.
Salvio sends the ball to Nelson Semedo but the Benfica wing-back loses the ball 30 yards out down the right.
Dortmund are in their usual yellow shirts and black shorts, Benfica in red shirts and white shorts kick off. The home side are likely to line up with a , Benfica will play a , with Andre Almeida and Andreas Samaris in the holding role.
Dortmund midfielder Gonzalo Castro believes his side were the better team in the first leg despite the narrow defeat.
But we will have to be wary not to concede at home, or things will get really difficult," he said. Pierre-Emerick Aubameyang missed a penalty for Dortmund in the first leg, but Tuchel says his players must put aside any negative thoughts from the Estadio da Luz.
Benfica is not only a big name. Group Stage Arsenal - Sporting Lissabon. Game finished - Arsenal 0, Sporting CP 0. Matteo Guendouzi - Arsenal - won a free kick on the left wing.
Offside - Sporting CP. Jovane Cabral - Sporting CP - won a free kick in attack. Fouled by Alex Iwobi - Arsenal. Matteo Guendouzi - Arsenal - won a free kick in defence.
Pierre-Emerick Aubameyang - Arsenal - shot with right foot from outside the box goes high from a free kick. Jeremy Mathieu - Sporting CP - receive red card.
Pierre-Emerick Aubameyang - Arsenal - won a free kick in attack. Substitution - Sporting CP. Jovane Cabral for Abdoulaye Diaby.
Pierre-Emerick Aubameyang - Arsenal - shot with right foot from the centre of the box is blocked. Assist - Sead Kolasinac. Henrikh Mkhitaryan - Arsenal - shot with right foot from the centre of the box is saved in the right corner.
Assist - Alex Iwobi. Bruno Gaspar with a pass, however Abdoulaye Diaby is in offside. Corner - Sporting CP. Conceded by Henrikh Mkhitaryan.
Abdoulaye Diaby - Sporting CP - shot with left foot from outside the box is blocked. Assist - Bruno Fernandes.
Ainsley Maitland-Niles for Stephan Lichtsteiner - injury. Sokratis - Arsenal - won a free kick in defence. They are ready to continue. Delay in match Stephan Lichtsteiner - Arsenal - - injury.
Matteo Guendouzi - Arsenal - receive yellow card for a foul. Nani - Sporting CP - won a free kick in defence. Fouled by Matteo Guendouzi - Arsenal.
Emile Smith-Rowe - Arsenal - won a free kick in defence. Bas Dost for Fredy Montero. Alex Iwobi - Arsenal - shot with right foot from outside the box goes high.
Assist - Sead Kolasinac after corner. Matteo Guendouzi - Arsenal - shot with right foot from outside the box is blocked. Stephan Lichtsteiner - Arsenal - won a free kick in defence.
Fouled by Nani - Sporting CP. Aaron Ramsey - Arsenal - won a free kick in attack.