Peterborough United goalkeeper Joe Lewis will play no further part in the League One play-offs after a scan revealed he has fractured his knee cap.
Lewis, 23, was substituted at half-time in Sunday's 3-2 semi-final first leg defeat by MK Dons.
"It is a big blow to miss the play-offs and my main aim is to be fit for pre-season," he told the club website.
Defender Gabby Zakuani is expected to recover from a shoulder injury to face the Dons on Thursday.
The 24-year-old had not suffered a dislocated shoulder as initially feared, but he may need to use a pain-killing injection to feature.
"Gabby will be fit, he'll be OK," Ferguson told BBC Radio Cambridgeshire.
Second choice goalkeeper Paul Jones, who conceded all three Dons goals in the second half of the first leg, will step up to replace Lewis.
"I have no doubt Paul will be able to handle the play-offs," Lewis added.
"I am convinced he has the ability and mental strength to cope with the pressure."
Posh boss Ferguson will also be without Charlie Lee at left-back, who will be suspended after being sent off for two bookable offences at Stadium MK.
Grant Basey should have recovered from an ankle injury in time to slot in.
"Grant's fine, he's trained for over a week, he was a couple of sessions short for Sunday," Ferguson added.
"We've got him to choose or Tommy Rowe could play there, I have got options, it's been a position that's been a problem most of the season."