Borussia Dortmund coach Jurgen Klopp has admitted that his side must work on their fitness before the start of the new Bundesliga season.
BVB finished third in the Telekom Cup with a 1-0 win over Hamburger SV, and Klopp said that although Dortmund played some good football, his players got tired too quickly.
"We have gained many insights," Klopp told Bundesliga.de. "The timing, and the pressing off the ball are not quite there. But that's not unusual. We have to work.
"Many things were good and we played some really nice football. Physically we tired and we were not even at the limit. Football-wise it was fine."
Dortmund finished second in the Bundesliga last season and were also beaten Champions League finalists.