Klopp: I'm surprised United sold Kagawa

The German has revealed he didn't expect Louis Van Gaal to allow the Japan international to leave Old Trafford

Borussia Dortmund boss Jurgen Klopp has admitted that he was surprised that Manchester United were willing to let Shinji Kagawa leave the club.

The Japan international left BVB for Old Trafford two years ago but returned to his old club after two frustrating seasons in England and marked his second debut with a goal in Saturday's win over Freiburg.

"I was kind of surprised Kagawa was on the market again," he told reporters.

"His first year at Manchester United was Sir Alex Ferguson's last year, so that isn't the time to develop players. The only thing you want at that stage is results and titles.

"Kagawa's second year at United was the first year of the new coach, so that's also all about results. Then there was a third manager with a very successful philosophy [Louis van Gaal].

"So we saw the chance to sign Kagawa and we took it. Kagawa was sensational against Freiburg."

BVB take on Arsenal in their opening Champions League game on Tuesday and Klopp believes the addition of Alexis Sanchez will see them play more offensively than they did when the two teams met last term.

 "Arsenal have new players in their squad and the last time we played them they had players with injuries like Jack Wilshere and Aaron Ramsey," he said.

"Now they have new players like Alexis Sanchez. Olivier Giroud can't play but when you look at their squad they have a lot of alternatives.

"Arsenal played very defensively here last year. But you have to say that our Champions League is starting against a great team. Arsenal are a very hard opponent and I think they did a great job on transfers over the summer.

"Now their squad has great stability and they're actually able to play the type of football that Arsene Wenger wants to see.