Borussia Dortmund midfielder Emre Can says his new side have to learn to “play dirty” at times as they look to bounce back from successive defeats.
Lucien Favre’s side flew out of the blocks after the Bundesliga winter break last month, scoring five goals in successive wins against Augsburg, Cologne and Union Berlin.
However, they have been brought down to earth with a bump over the past week, first losing 3-2 at Werder Bremen in DFB-Pokal before a 4-3 Bundesliga defeat at Bayer Leverkusen on Saturday.
Can made his Dortmund debut as a late substitute in the Bremen defeat following his January move from Juventus, before making his first start in the weekend loss at Leverkusen.
And after conceding seven goals in two games, the 26-year-old says defending is an obvious area of improvement, which he believes includes the use tactical fouls to break up play and deny opposition attacks.
“We conceded goals too easily. I've only been here for a week but this team, which was enormous potential, has to learn one thing: to put it crudely, we have to play dirty sometimes and commit fouls if we have to,” Can told Sky Germany.
“Everyone has to defend together. We all have to get better defensively as a unit, from front to back. I don't just mean the goalkeeper or the defenders, I mean everyone.
“It's a setback for us but the season still has a long time to go. I believe in this team, I've realised that in my short time training with them. I'll definitely be throwing myself into my work to help the team, because I can play better as well. You'll see that in the future.”
Dortmund led Leverkusen 3-2 going into the final 10 minutes at the BayArena, but two goals in as many minutes from Leon Bailey and Lars Bender condemned them to defeat.
Reflecting on the Leverkusen result, sporting director Michael Zorc said: “It hurts! It's just very disappointing because we played a good game until the 80th minute and deserved the lead.
“Then we were just too passive at the crucial moments and allowed Leverkusen to turn the game. It was clear that Bayer had offensive quality, too, but we simply gave up on all four goals.
“At home we are an absolute power, winning most games confidently. That's a fact. Part of our problem is that we can't do it away from home - even if we play like we normally do for long periods.
“We have to make sure that we stop conceding so many goals.”