Dortmund is interested in signing Axel Witsel according to reports. Witsel is currently playing for Tianjin Quanjian in China and signed with the team in 2017. According to Funke, he is at the top of the list for Favre and Zorc at the moment and they are pursuing a transfer.
Witsel was impressive for Belgium at the World Cup, starting six of the seven matches and playing a pivotal midfield role for the bronze medal winners. International play is really the only opportunity to see Witsel at his best as he has not played in a top five league in his career. Witzel played for Standard Liege in Belgium, moved to Benfica and then Zenit Saint Petersburg before landing in China.
At age 29, Witsel could be looking to finally make that step to an upper tier club with Borussia Dortmund before it is too late. He almost certainly has an enormous contract in China, but would likely be willing to take a pay cut if he is indeed interested in joining and taking his career too the next level.
For Dortmund this would be both a great and complicated signing. Witsel is an underrated player and would immediately strengthen the midfield for Dortmund. He would also be coming to Dortmund in the middle of his prime years and would not be a flight risk like some of their younger stars, something the team has been lacking recently.
It would also complicate the midfield, however. With Delaney, Dahoud, Weigl, Gotze, and Kagawa all looking for major minutes in various midfield roles, it would be hard to imagine keeping all of them heading into the season if this transfer was completed. It is likely that Weigl or Dahoud would be the odd man out and playing for another club come the start of the season.