An embarrassing ticketing bungle has allowed non-NRL club members to purchase tickets for Saturday's highly-anticipated preliminary final between St George Illawarra and Wests Tigers.

The NRL on Monday ordered the temporary suspension of online sales on tickets, which were not supposed to go on sale to the general public until Tuesday morning.

A crowd of up to 70,000 is expected at ANZ stadium on Saturday night for the blockbuster, and the best seats were snapped up quickly on Monday morning - but they weren't all going to paid-up club members.

The NRL said a Ticketek technical glitch was to blame, and as a result members were not given exclusive buying rights to the grand final qualifier.

Sales through agencies and over the telephone were not affected, with the NRL pinning the blame firmly on Ticketek.

"Hopefully Ticketek can resolve this quickly," NRL chief operating officer Graham Annesley said on Monday.

"It is important that we do everything we can to protect the rights of club members."

Brought to you by AAP © 2024 AAP