A bonus-point defeat of Queensland at the Gabba has kept Tasmania's slim hopes of a one-day cup final appearance alive entering the final round.
The Tigers bowled the Bulls out for 150 on Thursday and chased down the total in just 27 overs with five wickets in hand.
Tasmanian opener Caleb Jewell (61 off 68 balls) batted with a rare freedom in otherwise tricky conditions.
Jewell's knock ensured there were few nervous moments for the visitors, who were 3-63 before he hit top gear to get the Tigers within striking distance.
Mac Wright (36 off 45) hit two sixes in his confident cameo, and Beau Webster was unbeaten on 20 off 17 deliveries.
Earlier Iain Carlisle (3-39) was the pick of Tasmania's bowlers, but it was Webster's double-strike to dismiss set pair Matthew Renshaw (16) and Max Bryant (32) that started the rot.
Fresh off a Shield century against the Tigers this week, Jack Clayton (24) set himself for another rescue mission.
But when he was bowled by Tom Rogers it triggered a lower-order collapse, the Bulls' last five wickets falling for just 10 runs.
The result left Queensland in second-last position ahead of the final round, while Tasmania - providing other results go their way - can jump from fourth into the grand final with a bonus-point defeat of third-placed Western Australia next week.