Mrozek had been on loan at Brommapojkarna in the Swedish first division for the past four months.
However, their season concluded, with the team finishing in 10th place thanks to Mrozek’s impact.
He played five times after his arrival, but the 21-year-old had to settle for a bench role more recently.
"He will stay in Liverpool," their sports director, Philip Berglund, told Swedish news outlet FotbollDirekt.
"We got into a situation with a bit of injuries and stuff this summer when he came and the initial plan has always been for him to go back to Liverpool after the season. Nothing has changed there.
"It's not easy to break through there (at Liverpool) and getting playing time as a young goalkeeper is extremely difficult. He probably got five games here during the autumn and it has been good for both parties."
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