Luis Diaz regained the lead for Liverpool midway through the second half before Josip Stanisic drew level at 3-3 in the 80th minute and Kratzig secured the win for Bayern at the death.
A left-back from Bayern’s youth system, Kratzig has impressed on the club’s pre-season tour of Asia and manager Thomas Tuchel was delighted with his performance on Wednesday when he was deployed in a more attacking position.
“Let’s not get overexcited but he’s a lovely guy,” said Tuchel.
“First of all, he has good character, is a very good football player and is very intelligent and smart on the pitch.
“He was very strong when we changed him into an offensive position. I didn’t know how well he could play there because he’s usually a specialist defender,” Tuchel added.
“But he’s played well since day one of our tour in training and in our matches against Manchester City and Kawasaki Frontale in Tokyo, and today he finished in a very spectacular manner.”
Liverpool had trounced Leicester City 4-0 at the same venue last Sunday and they caught the German champions napping with their opening goal after 112 seconds.
Gakpo played a neat one-two with Diogo Jota on the halfway line and surged past the Bayern defence before firing past Yann Sommer into the roof of the net.
