Sunderland have taken the decision to reduce Portsmouth's away allocation by over a third.
It is understood the reduced allocation is a direct consequence of the pyrotechnic launched from the Portsmouth end which landed in Sunderland’s family section during the clash between the sides last month.
18-year-old Portsmouth supporter Samuel Parrott was subsequently charged with the throwing of missiles at a designated sporting event and Sunderland have now acted upon the advice of their safety advisory group by cutting Portsmouth's allocation.
It means Portsmouth have been given 2,000 tickets for Saturday's first leg of the League One play-off semi-finals at the Stadium of Light. 1,122 less than they received for the league fixture.
However, Portsmouth chief executive Mark Catlin is hopeful their allocation will be increased before Saturday.
He told Portsmouth News: "Obviously our ticket allocation is a decision for Sunderland – and I believe it to be as a result of their safety advisory group’s recommendation.
"We are in constant contact to see if we can get that increased but, unfortunately, our last game had a few incidents and I believe that has had an adverse effect.
"From my understanding, before our last game at Sunderland, the club were very nervous as a result of what happened with Coventry.
"The information is there were then some widely-reported incidents from our recent fixture – and their safety advisory group have subsequently taken the decision to just give us 2,000 tickets.
"It is under review, we are still working with Sunderland on it, and hopefully that can be increased.
"When it comes to the safety advisory group, the club (Sunderland) have an input but don’t have the final say. We have no input, it is down to the home club and the safest way they feel they can manage a game at their stadium.
"When we played there, there were a number of incidents on the day. Not all were necessarily Pompey-related, however, concerns have been raised.
"It’s Sunderland’s event, 2,000 tickets is the minimum requirement, which they have met, and really it is down to them. There’s not a lot we can influence."
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