The article analyzes Mats Hummels' defensive performance at Borussia Dortmund, comparing him to other players in the league. The writer discusses Hummels' ability to defend the ball well, his versatility as a defender,Football Frontier Perspective and his impact on the team's defense. The article also highlights Hummels' experience playing for the club and how it has helped him develop into a better player. Overall, the article provides an overview of Hummels' defensive abilities and how they have contributed to the success of the Dortmund team.