As the UEFA Champions League group stages reach their halfway stage, there will be a crunch match in Lisbon on Tuesday night as Sporting CP and Borussia Dortmund go head-to-head in Group F.

With defending champions Real Madrid the favourites to top the group, these two are presumably battling it out for second spot, although Dortmund have the edge following their draw with the Spaniards in their last match

With two back-to-back games coming up, whoever comes out on top will be in pole position to progress. A victory for either side here could prove decisive.

Dortmund lead the way in the group

As it stands Dortmund are top of Group F with four points, with the six goals they scored against Legia Warsaw in their opening game given them the advantage over Real Madrid, who they drew 2-2 with three weeks ago.

Sporting came within minutes of beating Real in their opening game, before a dramatic late comeback by the European champions, however like Dortmund they have also beaten Legia.

Dortmund don’t come into the game in the greatest of form and a without a win in three matches. They have been hit by a spate of injuries, and after losing to Bayer Leverkusen before the international break, they drew 1-1 with Hertha BSC on Friday night, leaving them fifth in the Bundesliga table, four points off the top.

Sporting are third in Liga Nos, three points adrift of leaders SL Benfica. Their last league game ended in a 3-3 draw with Vitória SC, with their first game following the internationals a cup tie against second-tier FC Famalicão , with a narrow 1-0 win thanks to a Lazar Marković goal.

The two sides have never met before in UEFA competition, however Sporting have a poor record against German sides, with just two victories. They have been knocked out of the UEFA Europa League in the last two seasons by VfL Wolfsburg and Leverkusen. Dortmund have five wins in eight encounters with sides from Portugal, including a knockout victory against Porto in last year’s Europa League.

A crunch game in the group

Jorge Jesus, who will be serving the second game of a touchline ban, revealed that the team had “put a lot of thought” into how they will approach the match. “We are playing one of the strongest teams in Europe,” he said. “They are a very strong team offensively.”

Thomas Tuchel is confident ahead of the match, despite the team’s dip in form and considerable injury problems, with at least nine players missing. "I have strong players available and I am fully confident in the team I will put out tomorrow,” he said in Monday’s press conference. “My young players assume their responsibility. They are professionals, they are dedicated, talented and have great ambition.”

The matches over the next couple of weeks could be decisive in deciding who goes through to the last 16, and Tuchel is aware of the test that awaits. They are strong technically, robust defensively and with [former Wolfsburg striker] Bas Dost up front, are dangerous in attack,” he said.

Jesus agrees with his counterpart about the importance of the game, saying it “could be a decisive one for both teams’ chances.” However he is confident in his side. “My players are going to give everything they have as they look to win,” he said. “We have total confidence in our own capabilities.”

Not just Dortmund with injury concerns

Although there’s more to be said about Dortmund’s injury crisis, Sporting have injury concerns of their own. Their captain Adrien Silva is out after undergoing knee surgery, whilst Jefferson and Radosav Petrović are also ruled out.

Centre-back Ruben Semedo has also had a thigh injury, which he picked up whilst with the Portugal under-21s, however there is hope that he will be fit to play.

Dortmund had ten players missing with injury against Hertha, including key players such as Marco Reus, André Schürrle and Gonzalo Castro. And their problems got with Marcel Schmelzer ruled out for three weeks after picking up an adductor injury in that game. His replacement in that match, Joo-Ho Park, is not in their Champions League squad.

There is better news though, with defenders Sokratis and Lukasz Piszczek likely to be available injuries sustained on international duty. “[They] have trained without discomfort and there is justified hope that they can play tomorrow," said Tuchel.

Marc Barta should also be ready to start, having been an unused substitute on Friday following his abductor injury, although with Matthias Ginter available to him, Tuchel may decide against taking the risk with Sokratis.

Predicted line-ups

Borussia Dortmund: (4-1-4-1) Bürki; Piszczek, Ginter, Bartra, Passlack; Weigl; Dembélé, Kagawa, Götze, Pulisic; Aubameyang.

Sporting CP: (4-2-3-1) Patrício; Pereira, Coates, Semedo, Zeegelaar; Elías, Carvalho; Martins, Ruiz, César; Dost.

Quotes via UEFA.