ACL has secured the last spot in the TCL Premier League's final four, ending Trevallyn's slim hopes in the process.
A lacklustre campaign had forced Trevallyn to win all its last three fixtures to reach the semi-finals all the while ACL required one more victory to go some way to avenge missing out narrowly last year.
Trevallyn worked its way to 6-159 in setting a target.
Captain James Whiteley hit 10 fours to carry his bat for a resolute 78, but found little support at the other end.
The opener had combined for 43 with Clade White for the third wicket, but still the hosts battled for momentum on Saturday after White was given out leg before for 24.
Ian Labrooy broke up the partnership and the next two wickets to finish with 3-35.
ACL cruised towards the emphatic seven-wicket win after openers Jesse Digney (21) and John Kedey (24) got their side to 2-74 early on.
Chathura Athukorala took over, adding 62 before Kieran Davey saw the Bluebacks to victory at the start of the 36th over with an unbeaten 46.
Longford has gone on to keep its unbeaten run intact, but their defence was threatened late by Beaconsfield.
Still riding a high from a T20 statewide triumph over Launceston, the Tigers managed 8-210 off their 40 overs.
After Tigers captain Jackson Blair fell for a quickfire 23 and coach Josh Adams for a more subdued seven, Yeshan Wickramarachchi then launched the innings with a superb 107 off 95 balls that included 10 fours and a six.
Dion Blair contributed 42 to the 128-run stand with the Sri Lankan off 141 deliveries.
Swans skipper Sean Barry provided leadership through the onslaught though to capture 3-22 from eight overs.
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Beaconsfield had got off to a scratchy start, falling to 3-50 inside the 14th over.
Keeper Nathan Berry soon strolled out and got right on top of the Tigers attack with a much-needed 34 off 32 balls.
But the end of the 53-run stand with Tyler Bain (26) also sparked the loss of three quick wickets for 13 runs.
The home side required 95 runs off 70 balls and looked gone five wickets down until Sean Barry and Nathan Lewis combined for 41 in 25 balls.
Lewis was dismissed for a 13-ball 20 when the equation was reduced to 54 off 45 balls.
But Tigers spearhead Max Magann tightened things up to keep the Swans to 7-192 - 19 runs short - with Barry left a near run-a-ball 37 not out.
Hadspen kept the pressure on ladder leaders Longford with a solid victory at Perth.
The home side had been bowled out for a par 161 after Ethan Goldfinch and Matt Lawrence both made 38 at the top of the Perth innings.
The 61-run partnership for the second wicket had the Demons on target for a big score at 1-78 in the 15th over.
But after both men were removed, the Demons were left to rue losing 5-24 in the middle-order. Seamer Kyle Strochnetter (5-22) captured consecutive five-fors following a 7-26 against Trevallyn.
Dilan Jayalath then piloted Hadspen to a win on the back of 60 off 41 with 11 fours.
Nathan Balym continued on to hit around 42 from 77 balls in sight of a six-wicket win with nine overs left.
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