IFFY ONUORA is facing an anxious trip to the specialist.
The 36-year-old striker suffered a knee injury when Town's substitutes were training on the Brisbane Road pitch in the minutes after Saturday's 1-1 draw.
The deadline-day arrival from Tranmere, whose Town return after 10 years has so far featured just three minutes against Swansea, fell to the ground in agony as Town coach Terry Yorath put the players through their paces.
Onuora's left knee became jarred and painful and he had to be helped from the field `piggy-back' style by physio Lee Martin.
"It is something which has happened to Iffy before, but the knee usually releases itself quite quickly and he is fine," said Martin.
"This time it was just locked and he has been struggling with his knee semi-bent without being able to get it straight.
"It is obviously something we are keen to check out as quickly as possible and hopefully it won't affect him too much, but at this stage it is a worry."
Should Onuora be sidelined, Jackson will have lost three strikers in one fell swoop with Andy Booth (one match) and Pawel Abbott (two) both facing bans when Scunthorpe United visit the McAlpine Stadium a week on Saturday, April 17.
With Jon Newby on loan at York, young John McAliskey was on the bench at Orient along with midfielder Gary Harkins, who made his League debut as replacement for Danny Schofield, and utility man Paul Scott.
Keeper Paul Rachubka has extended his loan from Charlton to the end of the season.