Gundogan was heavily linked with a summer transfer to Manchester United but signed a deal until 2016 with the Bundesliga outfit.
The Germany international played under Klopp at Dortmund, and his tweet on Saturday morning has triggered speculation that he could be set for a January move to the Merseyside outfit.
— Ilkay Gündogan (@Guendogan8) October 17, 2015
Klopp’s first game in charge of Liverpool ended in a goalless draw at White Hart Lane.
Liverpool return to action when they host Rubin Kazan in what will be new manager Klopp’s first home game in charge of his new club.
The Reds then host Southampton in the Premier League on Merseyside next weekend as they look to notch up their first top-flight win under the 48-year-old.
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