The Warriors won the right to host the play-off when they beat Zebre 54-0 at Scotstoun on Saturday, a result that meant they finished second in the PRO12 table. Around 600 tickets were sold at the ground immediately after the match, and plans were announced for a general sale to commence tomorrow morning.
However, with around 2700 season ticket holders having priority rights, and 2500 seats allocated to the away team, the number that can go on sale is already seriously diminished. On top of that, on Saturday evening the SRU sent out more than 100,000 emails to existing customers who have bought tickets - even if only for games at Murrayfield - in the past. A positive response rate of as little as five per cent would mean there would be no tickets left by tomorrow.
"That is certainly a possibility," said an SRU spokesman. "There is definitely the potential for a sell-out before Tuesday."
There have also been complaints from rugby followers who have tried to use the SRU's system that only uncovered seats seemed to be available for Friday's game. Others, though, have pointed out that Munster's allocation is being sold by online retailer Ticketmaster, and there are no restrictions on Scottish fans buying tickets by that route.
The spokesman confirmed that there are no plans to raise the semi-final capacity to 15,000 by re-erecting the temporary stands that were used for the Emirates Airline 7s the weekend before last. However, it is understood that these stands could be brought back if Glasgow earn the right to host the final on May 31.
For that to happen, the Warriors would clearly have to beat Munster on Friday, but Ulster would also have to win against Leinster in Dublin the following day. Having finished higher than Ulster in the league, Glasgow would be awarded home advantage for the final.