Australia's frontline white-ball spinner Adam Zampa claims the Big Bash League goes too long for fans as Cricket Australia braces for the possibility of another underwhelming finals crowd at the MCG on Thursday night.

Leggie Zampa and his Melbourne Stars' season will be on the line on Thursday night when they take on the Sydney Thunder in a cut-throat preliminary final, with the winners to take on the Sydney Sixers in Saturday's decider at the SCG.

Adam Zampa (left) takes a wicket against the Sixers in the Stars' opening final. Credit:AAP

Only 13,275 fans attended the Stars' qualifying final loss to the Sixers last Friday night, a crowd which Zampa labelled as "disappointing". Extreme heat and forecast storms didn't help CA's cause last weekend, although crowds and television ratings are down across the board this season.

In a bid to lure extra fans through the gates, all tickets have been kept to general admission prices for Thursday night while Stars members can enter for free with their membership card.