Maierhofer has undergone a hernia operation, but should be fit for the FA Cup fourth-round tie with Crystal Palace later this month.
A statement on his personal website read: “Stefan has a hernia – a protrusion on an organ in the groin which a small operation can resolve.
“So he flew to Munich on Thursday for a preliminary investigation and on Friday had the operation before flying back to England.
“Stefan is only expected to miss the Wigan game, after Sunday’s game with West Ham was postponed.”
