Borussia Dortmund v Borussia Moenchengladbach - Bundesliga
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Borussia Dortmund come into Wednesday's Champions League Group F clash with Club Brugge having beaten Zenit Saint Petersburg at home but needing another victory after the opening day loss to Lazio in Italy.

Although he will not be able to feature for the Germans in Belgium this midweek due to injury, Mats Hummels is back at Westfalenstadion for a second full-time spell -- this time as a figure of experience in a largely young and vibrant squad.

"My role is easy to define," Hummels told CBS Sports in an exclusive interview. "Leading first by example. Every day on the pitch I try to really work hard every day at training and of course talking to the teammates on and off the pitch."

The 31-year-old followed up the third and final goal in the Revierderby against Schalke with a heroic double against Arminia Bielefeld this past weekend for three goals from two Bundesliga outings, unfortunately being forced off injured toward the end of the latter fixture.

Despite the setback, Hummels is enjoying his second coming with Dortmund and stresses the importance of setting a strong example for his younger teammates.

"I try to do my best with my teammates," he said. "I hope in a good way to help the teammates, to get on that level.

"However, the most important thing is, you have to work hard, you have to be a role model when it comes to training, to the games because if you do not work hard yourself you cannot tell others to do of course."

Hummels, who rose to prominence with Dortmund as part of Jurgen Klopp's celebrated 2010-12 German champions and went on to enjoy great success with Bayern Munich and 2014 World Cup champions Germany, is now surrounded by exciting talents like Erling Haaland, Gio Reyna and Jadon Sancho.

Borussia Dortmund v Borussia Moenchengladbach - Bundesliga
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The man from Bergisch Gladbach has been impressed by the terrific trio and is convinced that the Norway international can maintain his prolific early career form.

"Incredible goalscorer and hard worker," Hummels said of Haaland. "I think that is something the people do not know because they see the work only on Tuesday, Wednesday and Saturday.

"They just see it on the pitch, but the work behind it is what makes him so good because he is working on himself. He knows what he can do, what his strengths are, but he knows his weaknesses as well and he is working on them.

"I am 100% convinced Erling will be one of the greatest goalscorers in the next 15 years, no question about it."

Hummels also played alongside current Bayern goal machine Robert Lewandowski in both Dortmund and Munich and rates the Polish star as the current leading figure in world football but applauds Haaland's efforts to keep pace with him.

"Lewy is the best player in the world for the last year," Hummels said. "I do not know if Erling can catch him, that depends on how healthy they stay, but I think if he is already compared to Lewy it shows how good he is, because for me, Lewy is the best in the whole world for the last 365 days."

On American soccer's new golden boy Reyna, who was called up for USMNT's November friendly vs. Wales, Hummels was effusive in his praise of the Sunderland-born and New York-raised phenom with a bright future for club and country.

"Great, great young player," he said. "I think there is no ceiling for him, no limits. It is up to him how good he will be.

"Gio is developing at an incredible pace. When he came to us in January, it was like 'Oh yeah, talented guy,' but of course still a little bit green behind the ears as we say.

"He learns very fast, he is getting better every week and if he keeps working like this and keeps playing the way he does and improving, we and I think the U.S. national team will have a pretty good player for a long time."

In addition to Haaland and Reyna, Hummels is playing alongside Sancho, and the seasoned veteran is convinced that the England international has what it takes to be of the best in the world.

"I think it is the same, almost the same, as what I said about Gio and Erling," the Common Goal ambassador said. "Incredibly talented of course. He has some things in his game that you do not see in many players in the world.

"His assisting on goals like he did against Schalke is almost perfect. The timing when he plays passes, the pace he plays passes with. He is very calm in front of the goal when he is scoring himself or when he is seeing other players. Of course, very good in dribbling.

"If he gets to show this on a daily basis, he can be one of the best players in the world and it is just up to him because he is not missing a lot of qualities you need for that."

Hummels will be hoping that Dortmund can return to Germany from Jan Breydel Stadium with Haaland, Reyna and Sancho having done the job for all three points in the first instalment of this important Champions League doubleheader. You can catch every Champions League match on CBS All Access.