The 45-year-old coach is confident that the club made an invaluable acquisition in the Germany international, who is worth more than his fee indicates.
The 45-year-old coach wasted no time in strengthening his striking options with the acquisition of the Germany international as a replacement for Shinji Kagawa, who left for Manchester United.
Reus, who represented his country at Euro 2012, rejoined his boyhood club for an equivalent sum of 17.5 million euros, a figure Klopp is now suggesting does not reflect the true value of the 23-year-old's talent.
"If we had signed Reus any later, he would have cost much more," Klopp explained to Bild. "We got him cheap, even if it was still for 17.5m euros.
"His market value is honestly much higher than what we paid for him, but it's not as if he feels any pressure - in fact, he doesn't seem to care, and neither do I."
Dortmund pipped Bayern Munich to the league title as well as the DFB-Pokal last season, and while Klopp was quick to assure fans that he was unfazed by the Bavarians' strengthening in the summer transfer window, he admitted they would be strong competitors for honors in the upcoming campaign.
"Bayern Munich's transfer campaign is only natural, where they are seizing every opportunity to reinforce, as are we and the likes of Borussia Monchengladbach, Schalke and Bayer Leverkusen," he said.
"The market is not yet closed yet, but Gladbach have invested fantastically, while Schalke had a very strong team last season. As always, they will mount a close fight for the title, in addition to us and Bayern."
Borussia Dortmund kicks off the first round of Bundesliga fixtures in defense of its title on Aug. 24 against Werder Bremen.
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